ML13175 [LANSDALE]
UHF FM/AM Transmitter; UHF调频/调幅发射机
| 型号： | ML13175 |
| 厂家： | 
LANSDALE SEMICONDUCTOR INC. |
| 描述： | UHF FM/AM Transmitter |
| 文件： | 总16页 (文件大小：579K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
ML13175
ML13176
UHF FM/AM Transmitter
Legacy Device: Motorola MC13175, MC13176
The ML13175 and ML13176 are one chip FM/AM transmitter subsys-
tems designed for AM/FM communication systems. they include a
Colpitts crystal reference oscillator, UHF oscillator, ÷ 8 (ML13175) or
÷ 32 (ML13176) prescaler and phase detector forming a versatile PLL
system. Targeted applications are in the 260 to 470MHz band and 902
to 982 MHz band covered by FCC Title 47; Part 15. Other applica-
tions include local oscillator sources in UHF and 900 MHz receivers,
UHF and 900 MHz video transmitters, RF Local Area Networks
(LAN), and high frequency clock drivers. ML13175/76 offer the fol-
lowing features;
ML13175-5P
PLASTIC PACKAGE
CASE 751B
16
(SO–16)
1
CROSS REFERENCE/ORDERING INFORMATION
• UHF Current Controlled Oscillator
• Uses Easily Available 3rd Overtone or Fundamental Crystals
for Reference
PACKAGE
MOTOROLA
LANSDALE
SO 16
SO 16
MC13175D
MC13176D
ML13175-5P
ML13176-5P
• Fewer External Parts Required
• Low Operating Supply Voltage (1.8 to 5.0 Vdc)
• Low Supply Drain Currents
• Power Output Adjustable (Up to + 10 dBm )
• Differential Output for Loop Antenna or Balun
Transformer Networks
Note: Lansdale lead free (Pb) product, as it
becomes available, will be identified by a part
number prefix change from ML to MLE.
• Power Down Feature
• ASK Modulated by Switching Output On and Off
• (ML13175) f = 8 x f , (ML13176) f = 32 x f
• Operating Temperature Range - T = -40° to +85°C
A
o
ref
o
ref
PIN CONNECTIONS
I
Osc 1
NC
1
2
3
4
5
6
7
8
16
15
14
mod
Out
Gnd
Figure 1. Typical Application as 320 MHz AM Transmitter
AM Modulator
Out 2
NC
1.3k
0.01
Osc
Tank
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
S
2
Osc 4
13 Out 1
µ
Coilcraft
150–05J08
V
V
12
11
10
9
V
CC
EE
(1)
Z = 50
EE
150p
0.165
µ
RF
SMA
Ω
out
I
Enable
Cont
f/N
RFC
EE
1
Reg.
Gnd
PD
out
(2)
V
S
V
CC
1
EE
0.1
µ
Xtalb
Xtale
150p
27k
1.0k
V
0.1µ
100p
(ML13176)
0.01
µ
30p
(ML13175)
ML13175–30p
ML13176–180p
ML13176
Crystal
V
0.82
µ
CC
(3)
ML13175
Crystal
Fundamental
10 MHz
V
1.0k
CC
3rd Overtone
40.0000 MHz
NOTES: 1. 50 Ω coaxial balun, 1/10 wavelength at 320 MHz equals 1.5 inches.
2. Pins 5, 10 & 15 are ground and connected to V which is the component/DC ground plane
EE
2. side of PCB. These pins must be decoupled to V ; decoupling capacitors should be placed
CC
2. as close as possible to the pins.
3. The crystal oscillator circuit may be adjusted for frequency with the variable inductor
3. (ML13175); recommended source is Coilcraft “slot seven” 7mm tuneable inductor, Part
3. #7M3–821. 1.0k resistor. Shunting the crystal prevents it from oscillating in the fundamental
3. mode.
Page 1 of 16
www.lansdale.com
Issue CcC
ML13175/ML13176
LANSDALE Semiconductor, Inc.
MAXIMUM RATINGS ( T = 25 C, unless otherwise noted.)
A
Rating
Symbol
Value
7.0 (max)
1.8 to 5.0
+150
Unit
Vdc
Vdc
C
Power Supply Voltage
V
CC
CC
Operating Supply Voltage Range
Junction Temperature
V
T
J
Operating Ambient Temperature
Storage Temperature
T
– 40 to + 85
– 65 to +150
C
A
T
stg
C
ELECTRICAL CHARACTERISTICS (Figure 2; V
= – 3.0 Vdc, T = 25 C, unless otherwise noted.)*
A
EE
Characteristic
Pin
–
Symbol
Min
– 0.5
–
Ty p
–
Max
–
Unit
µA
Supply Current (Power down: I & I = 0)
11 16
I
EE1
Supply Current (Enable [Pin 11] to V
CC
thru 30 k, I = 0)
16
–
I
–14
– 34
–18
–39
mA
mA
EE2
Total Supply Current (Transmit Mode)
(I = 2.0 mA; f = 320 MHz)
–
I
–
EE3
mod
o
Differential Output Power (f = 320 MHz; V [Pin 9]
13 & 14
P
out
dBm
o
ref
= 500 mV
; f = N x f
)
p–p
o
ref
I
I
= 2.0 mA (see Figure 7, 8)
= 0 mA
2.0
–
+ 4.7
– 45
–
–
mod
mod
Hold–in Range (± ±f x N)
ML13175 (see Figure 7)
ML13176 (see Figure 8)
13 & 14
7
± ±f
MHz
ref
H
3.5
4.0
6.5
8.0
–
–
Phase Detector Output Error Current
ML13175
ML13176
l
µA
error
20
22
25
27
–
–
Oscillator Enable Time (see Figure 22b)
11 & 8
16
t
–
–
4.0
25
–
–
ms
MHz
dBc
enable
BW
Amplitude Modulation Bandwidth (see Figure 24)
AM
Spurious Outputs (I
Spurious Outputs (I
= 2.0 mA)
= 0 mA)
13 & 14
13 & 14
P
P
–
–
– 50
– 50
–
–
mod
mod
son
soff
Maximum Divider Input Frequency
Maximum Output Frequency
–
f
–
–
950
950
–
–
MHz
div
f
o
13 & 14
* For testing purposes, V
CC
is ground (see Figure 2).
Figure 2. 320 MHz Test Circuit
I
mod
0.1
0.01
Osc
10k
1
2
3
4
5
6
7
8
16
Tank
µ
RF
out 1
15
14
13
12
11
10
9
Coilcraft
150–03J0
8
0.1
µ
V
µ
EE
(1)
51
0.098
µ
f/N
51
0.01µ
V
CC
(1)
RF
out 2
0.1
µ
I
reg. enable
30k
0.1
10k
27p
µ
0.01
µ
15p
(ML13176)
ML13175–30p
ML13176–33p
10p
(ML13175)
2.2k
ML13176
Crystal
Fundamental
10 MHz
0.82
µ
(3)
V
CC
ML13175
1.0k
Crystal
3rd Overtone
40 MHz
NOTES: 1. V
CC
is ground; while V is negative with respect to ground.
EE
2. Pins 5, 10 and 15 are brought to the circuit side of the PCB via plated through holes.
They are connected together with a trace on the PCB and each Pin is decoupled to V
3. Recommended source is Coilcraft “slot seven inductor ” part number 7M3–821.
(ground).
CC
Page 2 of 16
www.lansdale.com
IssueCCc
LANSDALE Semiconductor, Inc.
ML13175/ML13176
PIN FUNCTION DESCRIPTIONS
Internal Equivalent
Circuit
Description/External
Circuit Requirements
Pin
Symbol
1 & 4
Osc 1,
Osc 4
CCO Inputs
V
CC
The oscillator is a current controlled type. An external oscillator
coil is connected to Pins 1 and 4 which forms a parallel
resonance LC tank circuit with the internal capacitance of the
IC and with parasitic capacitance of the PC board. Three
base–emitter capacitances in series configuration form the
capacitance for the parallel tank. These are the base–emitters
at Pins 1 and 4 and the base–emitter of the differential amplifier.
The equivalent series capacitance in the differential amplifier is
varied by the modulating current from the frequency control
circuit (see Pin 6, internal circuit). A more thorough discussion
is found in the Applications Information section.
10k
10k
1
4
Osc 4
0sc 1
5
6
V
Supply Ground (V )
EE
EE
V
EE
5
In the PCB layout, the ground pins (also applies to Pins 10 and
15) should be connected directly to chassis ground. Decoupling
Subcon
capacitors to V should be placed directly at
CC
the ground returns.
V
V
EE
EE
I
Frequency Control
For V = 3.0 Vdc, the voltage at Pin 6 is approximately 1.55
Cont
V
CC
CC
Vdc. The oscillator is current controlled by the error current from
the phase detector. This current is amplified to drive the current
source in the oscillator section which controls the frequency of
Reg
the oscillator. Figures 9 and 10 show the ±f
Figure 5 shows the ±f
osc
+ 85°C for 320 MHz. The CCO may be FM modulated as shown
in Figure 17, ML13176 320 MHz FM Transmitter. A detailed
discussion is found in the Applications Information section.
versus I ,
osc
Cont
6
Cont
versus I at – 40°C, + 25°C and
Cont
I
7
PD
Phase Detector Output
V
out
CC
The phase detector provides ± 30 µA to keep the CCO locked at
the desired carrier frequency. The output impedance of the
phase detector is approximately 53 kΩ. Under closed loop
conditions there is a DC voltage which is dependent upon the
free running oscillator and the reference oscillator frequencies.
The circuitry between Pins 7 and 6 should be selected for
adequate loop filtering necessary to stabilize and filter the loop
response. Low pass filtering between Pin 7 and 6 is needed so
that the corner frequency is well below the sum of the divider
and the reference oscillator frequencies, but high enough to
allow for fast response to keep the loop locked. Refer to the
Applications Information section regarding loop filtering and FM
modulation.
4.0k
4.0k
PD
out
7
Page 3 of 16
www.lansdale.com
Issue Cc
ML13175/ML13176
LANSDALE Semiconductor, Inc.
PIN FUNCTION DESCRIPTIONS
Internal Equivalent
Circuit
Description/External
Circuit Requirements
Pin
Symbol
8
Xtale
Crystal Oscillator Inputs
V
CC
The internal reference oscillator is configured as a common
emitter Colpitts. It may be operated with either a fundamental
or overtone crystal depending on the carrier frequency and the
internal prescaler. Crystal oscillator circuits and specifications
of crystals are discussed in detail in the applications section.
Xtalb
Xtale
8.0k
12k
9
8
With V
= 3.0 Vdc, the voltage at Pin 8 is approximately 1.8
CC
9
Xtalb
Vdc and at Pin 9 is approximately 2.3 Vdc. 500 to 1000 mVp–p
should be present at Pin 9. The Colpitts is biased at 200 µA;
additional drive may be acquired by increasing the bias to
approximately 500 µA. Use 6.2 k from Pin 8 to ground.
4.0k
10
11
Reg. Gnd
Enable
Regulator Ground
An additional ground pin is provided to enhance the stability of
the system. Decoupling to the V
should be done at the ground return for Pin 10.
V
CC
(RF ground) is essential; it
CC
Reg
5.0p
11
Enable
Device Enable
The potential at Pin 11 is approximately 1.25 Vdc. When Pin 11
is open, the transmitter is disabled in a power down mode and
draws less than 1.0 µA I
(i.e., it has no current driving it). To enable the transmitter a
if the MOD at Pin 16 is also open
CC
Subcon
current source of 10 µA to 90 µA is provided. Figures 3 and 4
show the relationship between I , V
and I
. Note
CC CC
reg. enable
2.4k
8.0k
that I is flat at approximately 10 mA for I = 5.0 to
CC
100 µA (I
.
reg enable
10
Reg. Gnd
= 0).
mod
12
V
CC
Supply Voltage (V
)
CC
The operating supply voltage range is from 1.8 Vdc to 5.0 Vdc.
In the PCB layout, the V trace must be kept as wide as
V
CC
CC
possible to minimize inductive reactances along the trace; it is
best to have it completely fill around the surface mount
components and traces on the circuit side of the PCB.
12
V
CC
13 & 14 Out 1 and
Out 2
Differential Output
The output is configured differentially to easily drive a loop
antenna. By using a transformer or balun, as shown in the
application schematic, the device may then drive an unbalanced
low impedance load. Figure 6 shows how much the Output
Power and Free–Running Oscillator Frequency change with
V
CC
temperature at 3.0 Vdc; I
= 2.0 mA.
mod
13
14
16
15
16
Out_Gnd
Output Ground
This additional ground pin provides direct access for the output
ground to the circuit board V
I
mod
Out 1
Out 2
.
EE
I
AM Modulation/Power Output Level
mod
The DC voltage at this pin is 0.8 Vdc with the current source
active. An external resistor is chosen to provide a source
current of 1.0 to 3.0 mA, depending on the desired output power
level at a given V . Figure 23 shows the relationship of Power
CC
15
Out_Gnd
Output to Modulation Current, I
power output can be acquired with about 35 mA I
. At V
= 3.0 Vdc, 3.5 dBm
mod CC
.
CC
For FM modulation, Pin 16 is used to set the desired output
power level as described above.
For AM modulation, the modulation signal must ride on a
positive DC bias offset which sets a static (modulation off)
modulation current. External circuitry for various schemes is
further discussed in the Applications Information section.
Page 4 of 16
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Issue c
LANSDALE Semiconductor, Inc.
ML13175/ML13176
Figure 3. Supply Current
versus Supply Voltage
Figure 4. Supply Current versus
Regulator Enable Current
100
10
10
8.0
6.0
4.0
2.0
0
I
I
= 90 µA
reg. enable
= 0
mod
V
mod
= 3.0 Vdc
= 0
CC
I
1.0
0.1
0
1.0
2.0
3.0
4.0
5.0
1.0
10
100
1000
V
, SUPPLY VOLTAGE (Vdc)
I
, REGULATOR ENABLE CURRENT (µA)
CC
reg. enable
Figure 5. Change Oscillator Frequency
versus Oscillator Control Current
Figure 6. Change in Oscillator Frequency and
Output Power versus Ambient Temperature
10
4.0
3.0
5.5
5.0
V
= 3.0 Vdc
= 2.0 mA
±f
osc
P
CC
O
I
mod
f = 320 MHz (I
= 0; T = 25 °C)
A
5.0
0
Cont
2.0
1.0
0
Free–Running Oscillator
4.5
4.0
– 40 °C
25 °C
– 5.0
–1.0
– 2.0
– 3.0
– 4.0
V
I
= 3.0 Vdc
= 2.0 mA
CC
3.5
3.0
–10
–15
mod
f = 320 MHz (I
= 0; T = 25 °C)
A
Cont
Free–Running Oscillator
85 °C
– 50
0
50
100
– 40
– 20
I
0
20
40
60
A)
80
T , AMBIENT TEMPERATURE (°C)
, OSCILLATOR CONTROL CURRENT (
µ
A
Cont
Figure 7. ML13175 Reference Oscillator
Frequency versus Phase Detector Current
Figure 8. ML13176 Reference Oscillator
Frequency versus Phase Detector Current
41.0
10.3
10.2
Closed Loop Response:
Closed Loop Response:
V
f
ref
= 3.0 Vdc
V
f
ref
= 3.0 Vdc
40.8
40.6
40.4
CC
CC
= 8.0 x f
= 32 x f
o
ref
o
ref
V
= 500 mV
V
= 500 mV
p–p
p–p
10.1
10
I
I
= 1.0 mA
mod
40.2
= 22 mA
CC
I
I
= 1.0 mA
mod
P
= –1.1 dBm
O
= 25 mA
40.0
39.8
39.6
CC
P
= – 0.2 dBm
O
I
I
= 2.0 mA
I
= 2.0 mA
mod
9.9
9.8
mod
= 36 mA
I
= 35.5 mA
= 4.7 dBm
CC
CC
P
= 5.4 dBm
P
O
O
– 30
– 20
–10
0
10
20
30
– 30
– 20
–10
0
10
20
30
I , PHASE DETECTOR CURRENT (µA)
I , PHASE DETECTOR CURRENT (µA)
7
7
Page 5 of 16
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Issue c
ML13175/ML13176
LANSDALE Semiconductor, Inc.
Figure 10. Change in Oscillator Frequency
versus Oscillator Control Current
Figure 9. Change in Oscillator Frequency
versus Oscillator Control Current
20
10
20
10
V
I
= 3.0 Vdc
= 2.0 mA
V
I
= 3.0 Vdc
= 2.0 mA
CC
CC
mod
mod
0
0
T
= 25 °C
T
= 25 °C
A
A
f
(I
) 320 MHz
f
(I
) 450 MHz
osc Cont @ 0
osc Cont @ 0
–10
– 20
–10
– 20
– 30
– 40
– 30
– 40
–100
0
100
200
300
400
500
A)
600
0
I
100
200
300
400
500
A)
600
–100
I
, OSCILLATOR CONTROL CURRENT (µ
, OSCILLATOR CONTROL CURRENT (µ
Cont
Cont
Legacy Applications Information
APPLICATIONS INFORMATION
EVALUATION PC BOARD
detector output and the frequency control input for the CCO.
However, this allows for characterization of the gain constants
The evaluation PCB, shown in Figures 26 and 27, is very versatile
and is intended to be used across the entire useful frequency range
of this device. The center section of the board provides an area for
attaching all SMT components to the component ground side of the
PCB (see Figures 28 and 29). Additionally, the peripheral area sur-
rounding the RF core provides pads to add supporting and interface
circuitry as a particular application requires. This evaluation board
will be discussed and referenced in this section.
of these loop components. The gain constants K , K and K
are well defined in the ML13175 and ML13176.
p
o
n
PHASE DETECTOR (Pin 7)
With the loop in lock, the difference frequency output of the
phase detector is DC voltage that is a function of the phase dif-
ference. The sinusoidal type detector used in the IC has the fol-
lowing transfer characteristic:
CURRENT CONTROLLED OSCILLATOR (Pins 1 to 4)
It is critical to keep the interconnect leads from the CCO (Pins 1
and 4) to the external inductor symmetrical and equal in length.
With a minimum inductor, the maximum free running frequency
is greater than 1.0 GHz. Since this inductor will be small, it may
be either a microstrip inductor, an air wound inductor or a tune-
able RF coil. An air wound inductor may be tuned by spreading
the windings, whereas tunable RF coils are tuned by adjusting
the position of an aluminum core in a threaded coilform. As the
aluminum core coupling to the windings is increased, the induc-
tance is decreased. The temperature coefficient using an alu-
minum core is better than a ferrite core. The UniCoil™ induc-
tors made by Coilcraft may be obtained with aluminum cores
(Part No. 51–129–169).
l = A Sin θ
e
e
The gain factor of the phase detector, K (with the loop in lock)
is specified as the ratio of DC output current, le to phase error,
p
θ
e:
l
K = /θ (Amps/radians)
p
e e
K = A Sin θ /θ
p
e e
Sin θ ~ θ for θ ≤ 0.2 radians;
e
e
e
thus K = A (Amps/radians)
p
Figures 7 and 8 show that the detector DC current is approxi-
mately 30 µA where the loop loses lock at θe = π/2 radians;
therefore K is 30 µA/radians.
p
CURRENT CONTROLLED OSCILLATOR, CCO (Pin 6)
Figures 9 and 10 show the non–linear change in frequency of
the oscillator over an extended range of control current for 320
and 450 MHz applications. K ranges from approximately
6.3x10 rad/sec/µA or 100 kHz/µA (Figure 9) to 8.8x10
rad/sec/µA or 140 kHz/µA (Figure 10) over a relatively linear
response of control current (0 to 100 µA). The oscillator gain
factor depends on the operating range of the control current
(i.e., the slope is not constant). Included in the CCO gain factor
is the internal amplifier which can sink and source at least
30µA of input current from the phase detector. The internal cir-
cuitry at Pin 6 limits the CCO control current to 50 µA of
source capability while its sink capability exceeds 200 µA as
shown in Figures 9 and 10. Further information to follow shows
how to use the full capabilities of the CCO by addition of an
GROUND (Pins 5, 10 and 15)
o
GROUND RETURNS: It is best to take the grounds to a back-
side ground plane via plated through holes or eyelets at the pins.
The application PCB layout implements this technique. Note
that the grounds are located at or less than 100 mils from the
device pins.
5
5
DECOUPLING: Decoupling each ground pin to V
each section of the device by reducing interaction between sec-
tions and by localizing circulating currents.
isolates
CC
LOOP CHARACTERISTICS (Pins 6 and 7)
Figure 11 is the component block diagram of the ML1317x PLL
system where the loop characteristics are described by the gain
constants. Access to individual components of this PLL system
is limited, inasmuch as the loop is only pinned out at the phase
external loop amplifier and filter (see Figure 15). This addition-
al circuitry yields at K = 0.145 MHz/µA or 9.1x10
rad/sec/µA.
5
o
Page 6 of 16
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Issue c
LANSDALE Semiconductor, Inc.
ML13175/ML13176
Legacy Applications Information
Figure 11. Block Diagram of ML1317x PLL
Phase
Detector
θ
θ
)
Low Pass
Filter
i(s)
e(s
f = f
i
ref
Pins 9,8
K
f
Where: K = Phase detector gain constant in
Pin 7
p
K
= 30
µA/rad
p
= µA/rad; K = 30 µA/rad
= Filter transfer function
p
K
K
K
f
θ
=
θ
)/N
= 1/N; N = 8 for the MC13175 and
= 1/N; N = 32 for the MC13176
= CCO gain constant in rad/sec/µA
f
= f /N
o
n(s)
o(s
n
o
n
Pin 6
Divider
= 1/N
Amplifier and
Current Controlled
Oscillator
5
= 9.1 x 10 rad/sec/µA
K
o
θ
o(s)
K
n
N = 8 : ML13175
N = 32 : ML13176
K
= 0.91Mrad/sec/µA
o
Pins 13,14
f
= nf
i
o
LOOP FILTERING
The fundamental loop characteristics, such as capture range,
For L = 0.707 and lock time = 1.0 ms;
then ω = 5.0/t = 5.0 krad/sec.
loop bandwidth, lock–up time and transient response are con-
trolled externally by loop filtering.
The loop filter may take the form of a simple low pass filter
or a lag–lead filter which creates an additional pole at origin
in the loop transfer function. This additional pole along with
that of the CCO provides two pure integrators (1/s2). In the
lag–lead low pass network shown in Figure 13, the values of
The natural frequency (ω ) and damping factor (L ) are
n
important in the transient response to a step input of phase or
frequency. For a givenL and lock time wn can be determined
from the plot shown in Figure 12.
the low pass filtering parameters R , R and C determine the
1
2
loop constants ω and L. The equations t =R C and t =R C
n
1
1
2
2
are related in the loop filter transfer functions
F(s) = 1 +
Figure 12. Type 2 Second Order Response
t s/1 + (t +t )s.
2
1 2
1.9
1.8
Figure 13. Lag–Lead Low Pass Filter
ζ
= 0.1
1.7
1.6
1.5
1.4
1.3
V
R
V
O
in
1
R
2
0.2
C
0.3
0.4
The closed loop transfer function takes the form of a 2nd
order low pass filter given by,
1.2
1.1
1.0
0.5
H(s )= K F(s)/s + K F(s)
v
v
From control theory, if the loop filter characteristic has F(0) =
1, the DC gain of the closed loop, K is defined as,
0.6
0.7
v
0.8
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
K = K K K
v
p o n
and the transfer function has a natural frequency,
ωn = K /t + t )1/2
1.5
2.0
v 1
2
and a dampning factor,
L
= (ω /2) (t + 1K )
Rewriting the above equations and solving for the ML13176
n
2
v
L
v
1
2
with
= 0.707 and ω = 5.0 k rad/sec.
n
K = K K K = (30) (0.91 X 106)(1/32) = 0.853 X 106
p o n
t + t = K /ω 2 = 0.853 X 106/(25 X 106) = 34.1 ms
2
v n
3
L
t = 2 /ω = (2)(0.707)/(5 X 10 ) = 0.283 ms
n
t = (K /ω 2) –t =(34.1–0.283) = 33.8 ms
1
v n
2
0
1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10 11
12 13
ω
nt
Page 7 of 16
www.lansdale.com
Issue c
ML13175/ML13176
LANSDALE Semiconductor, Inc.
Legacy Applications Information
For C = 0.47 µ:
through 8 are a direct measurement of the hold–in range (i.e.
–3
– 3
–6
–6
then R = t /C = 33.8 X 10 /0.47 X 10 = 72 k
±f x N = ±f x 2π). Since sin θ cannot exceed 1.0, as θ
1
2
1
2
ref e
H
e
thus, R = t /C = 0.283 X 10 /0.47 X 10 = 0.60k
approaches π/2 the hold–in range is equal to the DC loop gain
K X N.
In the above example, the following standard value components
are used,
v
±ω = K x N
H
v
C = 0.47 µf; R = 620 and R’ = 72 kΩ – 53 kΩ ~ 18 kΩ
where, K = K K K
2
1
v
p o n.
(R’ is defined as R – 53 kΩ, the output impedance of the phase In the above example,
1
1
detector.)
±ω = 27.3 Mrad/sec
H
±f = 4.35 MHz
H
Since the output of the phase detector is high impedance (~50 k)
and serves as a current source, and the input to the frequency con- EXTENDED HOLD–IN RANGE
trol, Pin 6 is low impedance (impedance of the two diode to
ground is approximately 500 Ω), it is imperative that the second
order low pass filter design above be modified. In order to mini-
The hold–in range of about 3.4% could cause problems over tem-
perature in cases where the free–running oscillator drifts more
than 2 to 3% because of relatively high temperature coefficients
mize loading of the R C shunt network, a higher impedance must of the ferrite tuned CCO inductor. This problem might worsen for
2
be established to Pin 6. A simple solution is achieved by adding a lower frequency applications where the external tuning coil is
low pass network between the passive second order network and
the input to Pin 6. This helps to minimize the loading effects on
the second order low pass while further suppressing the sideband
large compared to internal capacitance at Pins 1 and 4. To
improve hold–in range performance, it is apparent that the gain
factors involved must be carefully considered.
spurs of the crystal oscillator. A low pass filter with R = 1.0 k
3
and C - 1500 p has a corner frequency (f ) of 106 kHz; the ref-
K
= is either 1/8 in the ML13175 or 1/32 in the ML13176
= is fixed internally and cannot be altered.
c
n
2
erence sideband spurs are down greater than – 60 dBc.
K
p
o
K
= Figures 9 and 10 suggest that there is capability of
greater control range with more current swing. However,
this swing must be symmetrical about the center of the
dynamic response. The suggested zero current operating
point for 100 µA swing of the CCO is at about + 70
µA offset point.
Figure 14. Modified Low Pass Loop Filter
Pin 7
18kΩ
1.0kΩ
Pin 6
R'
1
R
3
R
620
2
C
1500pf
3
Ka = External loop amplification will be necessary since the
C
0.47
µf
phase detector only supplies 30 µA.
V
CC
HOLD–IN RANGE
The hold–in range, also called the lock range, tracking range and
In the design example in Figure 15, an external resistor (R ) of
5
15 kΩ to V
CC
(3.0 Vdc) provides approximately 100 µA of cur-
synchronization range, is the ability of the CCO frequency, f to
rent boost to supplement the existing 50 µA internal source cur-
rent. R (1.0 kΩ) is selected for approximately 0.1 Vdc across it
o
track the input reference signal, fref • N as it gradually shifted
4
away from the free running frequency, f . Assuming that the CCO with 100 µA. R , R and R are selected to set the potential at
f
1
2
3
is capable of sufficient frequency deviation and that the internal
Pin 7 and the base of 2N4402 at approximately 0.9 Vdc and the
emitter at 1.55 Vdc when error current to Pin 6 is approximately
loop amplifier and filter are not overdriven, the CCO will track
until the phase error, θe approaches π/2 radians. Figures 5
zero µA. C is chosen to reduce the level of the crystal sidebands.
1
Figure 15. External Loop Amplifier
V
= 3.0Vdc
CC
12
6
50µA
R
3
4.7k
R
15k
5
C
1000p
1
30µA
R
Oscillator
Control
Circuitry
4
1.6V
68k
R
R
1
1.0k
2N4402
Phase
Detector
Output
7
33k
2
30µA
5, 10, 15
Page 8 of 16
www.lansdale.com
Issue Cc
LANSDALE Semiconductor, Inc.
ML13175/ML13176
Legacy Applications Information
Figure 16 Shows the improved hold–in range of the loop. The ±fref
is moved 950 kHz with over 200 µA swing of control current for an
improved hold–in range of 15.2 MHz or 95.46 Mrad/sec.
f = 0.159/RC;
c
For R = 1.0 k + R (R = 53 k) and C = 390 pF
7
7
f = 7.55 kHz or ω = 47 krad/sec
c
c
Figure 16. ML13176 Reference Oscillator
Frequency versus Oscillator Control Current
The application example in Figure 17a of a 320 MHz FM transmitter
demonstrates the FM capabilities of the IC. A high value series resistor
(100 k) to Pin 6 sets up the current source to drive the modulation sec-
tion of the chip. Its value is dependent on the peak to peak level of the
encoding data and the maximum desired frequency deviation. The data
input is AC coupled with a large coupling capacitor which is selected
for the modulating frequency. The component placements on the circuit
side and ground side of the PC board are shown in Figures 28 and 29
respectively.
10.6
Closed Loop Response:
f
= 32 x f
o
ref
10.4
10.2
10
V
= 3.0 Vdc
CC
I
= 38 mA
= 4.8 dB
CC
P
out
I
= 2.0 mA
mod
V
= 500 mV
ref
p–p
9.8
For voice application using a dynamic or an electret microphone, an op
amp is used to amplify the microphone’s low level output . The micro-
phone amplifier circuit is shown in Figure 19. Figure 17b shows an
application example for NBFM audio or direct FSK in which the refer-
ence crystal oscillator is modulated.
9.6
9.4
–150
–100
– 50
0
50
A)
100
I , OSCILLATOR CONTROL CURRENT (
µ
6
Figure 19. Microphone Amplifier
LOCK–IN RANGE/CAPTURE RANGE
If a signal is applied to the loop not equal to free running frequency,
f , then the loop will capture or lock–in the signal by making f = f
o
V
Data
Input
f
s
CC
100k
120k
V
(i.e. if the initial frequency difference is not too great). The lock–in
range can be expressed as ±ω ~ 2L ω
CC
L
n
3.3k
1.0k
1.0
3.9k
10k
10k
FM MODULATION
Voice
Input
MC33171
Data or
Audio
Output
Noise external to the loop (phase detector input) is minimized by nar-
rowing the bandwidth. This noise if minimal in a PLL system since the
reference frequency is usually derived from a crystal oscillator. FM can
be achieved by applying a modulation current superimposed on the
control current of the CCO. The loop bandwidth must be narrow
Electret
Microphone
LOCAL OSCILLATOR APPLICATION
enough to prevent the loop from responding to the modulation frequen- To reduce internal loop noise, a relatively wide loop bandwidth is
cy components, thus, allowing the CCO to deviate in frequency. The
loop bandwidth is related to the natural frequency wn. In the lag–lead
design example where the natural frequency, ωn = 5.0 krad/sec and a
damping factor, L = 0.707, the loop bandwidth = 1.64 kHz.
Characterization data of the closed loop responses for both the
ML13175 and ML13176 at 320 MHz (Figures 7 and 8, respectively)
needed so that the loop tracks out or cancels the noise. This is empha-
sized to reduce inherent CCO and divider noise or noise produced by
mechanical shock and environmental vibrations. In a local oscillator
application the CCO and divider noise should be reduced by proper
selection of the natural frequency of the loop. Additional low pass fil-
tering of the output will likely be necessary to reduce the crystal side-
show satisfactory performance using only a simple low–pass loop filter band spurs to a minimal level.
network. The loop filter response is strongly influenced by the high
output impedance of the push–pull current output of the phase detector.
Page 9 of 16
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Issue c
ML13175/ML13176
LANSDALE Semiconductor, Inc.
Legacy Applications Information
Figure 17a. 320 MHz ML13176 FM Transmitter
RF Level Adjust
1.1k
5.0k
Osc
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
CC
Tank
0.047µ
CW
Coilcraft
146–04J08
(1)
50
SMA
RF Output
to Antenna
0.146
µ
Ω
510p
V
= 3.8 to
CC
3.3 Vdc
f/32
RFC (3)
1
0.1
µ
V
CC
0.47µ
(2)
V
9.1k
15k
EE
V
CC
27k
1.0k
130k
620
18k
2N4402
0.47µ
100k
33k
V
CC
Data Input
(1.6 Vp–p)
51p
220p
51p
6.8 (4)
Crystal
Fundamental
10 MHz
(5)
NOTES: 1. 50 Ω coaxial balun, 2 inches long.
2. Pins 5, 10 and 15 are grounds and connnected to V
These pins must be decoupled to V ; decoupling capacitors should be placed as close as possible to the pins.
which is the component's side ground plane.
EE
CC
3. RFC is 180 nH Coilcraft surface mount inductor or 190 nH Coilcraft 146–05J08.
1
4. Recommended source is a Coilcraft ™slot seven 7.0 mm tuneable inducto,rpart #7M3–682.
5. The crystal is a parallel resonant, fundamental mode calibrated with 32 pF load capacitance.
Figure 17b. 320 MHz NBFM Transmitter
RF Level Adjust
5.0k
1.0k
Osc
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
CC
Tank
0.047
µ
CW
Coilcraft
146–04J08
(1)
SMA
RF Output
to Antenna
0.146
µ
UT–034
470p
f/32
V
CC
RFC
(3)
0.1
µ
1
V
(3.6 Vdc – Lithium Battery)
CC
4700p
(2)
9.1k
15k
V
EE
V
CC
27k
1.0k
130k
6.2k
33k
15k
2N4402
0.47µ
V
V
RFC
CC
CC
2
1.0k
(4)
10p
External
Loop Amp
10µ
+
RFC
3
180p
100p
(6)
0.01
µ
Crystal
Fundamental
10MHz
(5) MMBV432L
Audio or
Data Input
NOTES: 1. 50 Ω coaxial balun, 2 inches long.
2. Pins 5, 10 and 15 are grounds and connnected to V
which is the component's side ground plane. These
EE
pins must be decoupled to V ; decoupling capacitors should be placed as close as possible to the pins.
CC
3. RFC is 180 nH Coilcraft surface mount inductor.
1
2
4. RFC and RFC are high impedance crystal frequency of 10 MHz; 8.2 µH molded inductor gives XL > 1000 Ω..
3
5. A single varactor like the MV2105 may be used whereby RFC is not needed.
2
6. The crystal is a parallel resonant, fundamental mode calibrated with 32 pF load capacitance.
Page 10 of 16
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Issue c
LANSDALE Semiconductor, Inc.
ML13175/ML13176
Legacy Applications Information
REFERENCE CRYSTAL OSCILLATOR
(Pins 8 and 9)
Figure 20. Crystal Equivalent Circuit
Selection of Proper Crystal: A crystal can operate in a num-
ber of mechanical modes. The lowest resonant frequency
mode is its fundamental while higher order modes are called
overtones. At each mechanical resonance, a crystal behaves
like a RLC series–tuned circuit having a large inductor and a
L
3
Cp
R
3
high Q. The inductor L is series resonance with a dynamic
s
C
3
capacitor, C determined by the elasticity of the crystal lattice
s
and a series resistance Rs, which accounts for the power dissi-
pated in heating the crystal. This series RLC circuit is in par-
the frequency separation at resonance is given by;
allel with a static capacitance, C which is created by the
p
1/2
±f = f –f = f [1 – (1+ C /C )
p s s p
]
crystal block and by the metal plates and leads that make con-
tact with it.
s
Usually f is less than 1% higher than fs, and a crystal
p
exhibits an extremely wide variation of the reactance with
Figure 20 is the equivalent circuit for a crystal in a signal res-
onant mode. It is assumed that other modes of resonance are
so far off frequency that their effects are negligible.
frequency between f and f . A crystal oscillator circuit is
p
s
very stable with frequency. This high rate of change of
impedance with frequency stabilizes the oscillator, because
any significant change in oscillator frequency will cause a
large phase shift in the feedback loop keeping the oscillator
on frequency.
Series resonant frequency, f is given by;
s
1/2
f = 1/2π(L C )
s
s s
and parallel resonant frequency, f is given by;
p
1/2
f = f (1 + C /C )
s p
p
s
Page 11 of 16
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Issue c
ML13175/ML13176
LANSDALE Semiconductor, Inc.
Legacy Applications Information
Manufacturers specify crystal for either series or parallel res-
onant operation. The frequency for the parallel mode is cali-
brated with a specified shunt capacitance called a “load
capacitance.” The most common value is 30 to 32 pF. If the
load capacitance is placed in series with the crystal, the
equivalent circuit will be series resonance at the specified
parallel–resonant frequency. Frequencies up to 20 MHz use
parallel resonant crystal operating in the fundamental mode,
while above 20 MHz to about 60 MHz, a series resonant
crystal specified and calibrated for operation in the overtone
mode is used.
R . enable = V
eg
– 1.0 Vdc/l . enable
reg
CC
From Figure 4, l
V
is chosen to be 75µA. So, for a
reg.enable
= 3.0 Vdc R
= 26.6 kΩ, a standard value 27
reg.enable
CC
kΩ resistor is adequate.
LAYOUT CONSIDERATIONS
Supply (Pin 12): In the PCB layout the V
kept as wide as possible to minimize inductive reactance
along the trace; it is best that V
fills around the surface mounted components and intercon-
nect traces on the circuit side of the board. This technique is
demonstrated in the evaluation PC board.
trace must be
CC
(RF ground) completely
CC
APPLICATION EXAMPLES
Two types of crystal oscillator circuits are used in the appli-
cations circuits: 1) fundamental mode common emitter
Colpitts (Figures 1, 17a, 17b and 21) and 2) third overtone
impedance inversion Colpitts (also Figures 1 and 21).
BATTERY/SELECTION/LITHIUM TYPES
The device may be operated from a 3.0 V lithium battery.
Selection of a suitable battery is important. Because one of
the major problems for long life battery powered equipment
is oxidation of the battery terminals, a battery mounted in
clip–in socket is not advised. The battery leads or contact
The fundamental mode common emitter Colpitts uses a par-
allel resonant crystal calibrated with a 32 pf load capacitance. post should be isolated from the air to eliminate oxide
The capacitance values are chosen to provide excellent fre-
quency stability and output power of > 500 mVp–p at Pin 9.
In Figures 1 and 21, the fundamental mode reference oscilla- given for the peak current capability of the battery. Lithium
build–up. The battery should have PC board mounting tabs
which can be soldered to the PCB. Consideration should be
tor is fixed tuned relying on the repeatability of the crystal
and passive network to maintain the frequency, while in the
circuit shown in Figure 17, the oscillator frequency can be
adjusted with the variable inductor for the precise operating
frequency.
batteries have current handling capabilities based on the com-
position of the lithium compound, construction and the bat-
tery size. A 1300 mA/hr rating can be achieved in the cylin-
drical cell battery. The Rayovac CR2/3A lithium–manganese
dioxide battery is a crimp sealed, spiral wound 3.0 Vdc, 1300
mA/hr cylindrical cell with PC board mounting tabs. It is an
The third overtone impedance inversion Colpitts uses a series excellent choice based on capacity and size (1.358” long by
resonance crystal with a 25 ppm tolerance. In the application 0.665” in diameter).
examples (Figures 1 and 21), the reference oscillator operates
with the third overtone crystal at 40.0000 MHz. Thus, the
ML13175 is operated at 320 MHz (f /8 = crystal; 320/8) =
40.0000 MHz. The resistor across the crystal ensures that the surface mount and radial–leaded components allows for sim-
crystal will operate in the series resonance mode. A tuneable
inductor is used to adjust the oscillation frequency; it forms a directly connected with bias via RFC or 50 Ω resistors.
parallel resonant circuit with the series and parallel combina- Antenna configuration will vary depending on the space
DIFFERENTIAL OUTPUT (Pins 13, 14)
The availability of micro–coaxial cable and small baluns in
o
ple interface to the output ports. A loop antenna may be
tion of the external capacitors forming the divider and feed-
back network and the base–emitter capacitance of the
devices. If the crystal is shorted, the reference oscillator
should free–run at the frequency dictated by the parallel reso- Amplitude Shift Key: The ML13175 and ML13176 are
nant LC network.
The reference oscillator can be operated as high as 60 MHz
with a third overtone crystal. Therefore, it is possible to use
the ML13175 up to at least 480 MHz and the ML13176 up to two or more values in response to the PCM code. For the
available and the frequency of operation.
AM MODULATION (Pin 16)
designed to accommodate Amplitude Shift Keying (ASK).
ASK modulation is a form of digital modulation correspon-
ding to AM. The amplitude of the carrier is switched between
950 MHz (based on the maximum capability of the divider
netowork).
binary case, the usual choice is On–Off Keying (often abbre-
viated OOK). The resultant amplitude modulated waveform
consists of RF pulses called marks, representing binary 1 and
spaces representing binary 0.
ENABLER (Pin 11)
The enabling resistor at Pin 11 is calculated by:
Page 12 of 16
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Issue c
LANSDALE Semiconductor, Inc.
ML13175/ML13176
Legacy Applications Information
Figure 21. ASK 320 MHz Application Circuit
R
mod
3.3k
(4)
Osc
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
On–Off Keyed Input
TTL Level 10 kHz
Tank
0.01µ
Coilcraft
150–05J08
V
(1)
EE
SM
A
0.165
µ
Z = 50
RF
Out
150p
f/N
RFC
1
(2)
EE
V
CC
V
0.1
µ
(5)
S
27k
1
150p
1.0k
V
EE
0.1
µ
ML13175–30p
ML13176–180p
0.01
µ
100p
(ML13176)
30p
(ML13175)
0.82
µ
(3)
ML13176
Crystal
V
CC
V
CC
ML13175
Fundamental
10 MHz
Crystal
1.0k
3rd Overtone
40.0000 MHz
NOTES: 1. 50 Ω coaxial balun, 1/10 wavelength line (1.5") provides the best
match to a 50 Ω load.
4. The On–Off keyed signal turns the output of the transmitter off and on with
TTL level pulses through R
by the resistor which sets I
at Pin 16. The "On" power and I
is set
mod
mod
CC
. (see Figure 23).
= VTTL – 0.8 / R
mod
2. Pins 5, 10 and 15 are ground and connnected to V
which is
the component/DC ground plane side of PCB. These pins must
EE
5. S1 simulates an enable gate pulse from a microprocessor which will
enable the transmitter. (see Figure 4 to determine precise value of the
enabling resistor based on the potential of the gate pulse and the
desired enable.)
be decoupled to V ; decoupling capacitors should be placed
CC
as close as possible to the pins.
3. The crystal oscillator circuit may be adjusted for frequency with
the variable inductor (MC13175); 1.0 k resistor shunting the
crystal prevents it from oscillating in the fundamental mode.
Recommended source is Coilcraft “slot seven” 7.0 mm tuneable
inductor, part #7M3–821.
Figure 21 shows a typical application in which the output
power has been reduced for linearity and current drain. The
enable time is needed to set the acquisition timing. It takes
typically 4.0 msec to reach full magnitude of the oscillator
current draw on the device is 16 mA I
(average) and –22.5 waveform. A square waveform of 3.0 V peak with a period
CC
dBm (average power output) using a 10 kHz modulating rate
for the on–off keying. This equates to 20 mA and –2.3 dBm
“on”, 13 mA and –41 dBm “Off”. The crystal oscillator
that is greater than the oscillator enable time is applied to the
Enable (Pin 11)
Page 13 of 16
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Issue c
ML13175/ML13176
LANSDALE Semiconductor, Inc.
Legacy Applications Information
ANALOG AM
Figure 23. Power Output versus Modulation Current
In analog AM applications, the output amplifier’s linearity
must be carefully considered. Figure 23 is a plot of Power
Output versus Modulation Current at 320 MHz, 3.0 Vdc. In
order to achieve a linear encoding of the modulating sinu-
soidal waveform on the carrier, the modulating signal must
amplitude modulate the carrier in the linear portion of its
power output response. When using a sinewave modulating
signal, the signal rides on a positive DC offset called Vmod
which sets a static (modulation off) modulation current,
10
5.0
0
V
= 3.0 Vdc
CC
f = 320 MHz
– 5.0
–10
–15
I
. I controls the power output of the IC. As the mod-
mod mod
ulating signal moves around this static bias point the modu-
lating current varies causing power output to vary or to be
AM modulated. When the IC is operated at modulation cur-
rent levels greater than 2.0 mAdc the differential output stage
starts to saturate.
– 20
– 25
0.1
1.0
, MODULATION CURRENT (mA)
10
I
mod
Page 14 of 16
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Issue c
ML13175/ML13176
LANSDALE Semiconductor, Inc.
Legacy Applications Information
In the design example, shown in FIgure 24, the operating
point is selected as a tradeoff between average power output
and quality of the AM.
Figure 24. Analog AM Transmitter
3.9kΩ 1.04Vdc 560
For V
= 3.0 Vdc;I
= 18.5 mA and Imod = 0.5 mAdc
CC
V
CC
16
0.8Vdc
CC
3.0Vdc
R
and a static DC offset of 1.04 Vdc, the circuit shown in
Figure 24 completes the design.
mod
Data
Input
800mVp–p
+
6.8µ
Where R
standard value resistor of 3.9 kΩ.
= (V
– 1.04 Vdc)/0.5 mA = 3.92 kΩ, use a
CC
mod
Page 15 of 16
www.lansdale.com
Issue c
ML13175/ML13176
LANSDALE Semiconductor, Inc.
OUTLINE DIMENSIONS
PLASTIC PACKAGE
(ML13175-5P, ML13176-5P)
CASE 751B
(SO–16)
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. DIMENSION A AND B DO NOT INCLUDE MOLD
PROTRUSION.
–A
–
4. MAXIMUM MOLD PROTRUSION 0.15 (0.006)
PER SIDE.
5. 751B–01 IS OBSOLETE, NEW STANDARD
751B–03.
16
1
9
8
M
M
P
C
0.25 (0.010)
B
–B
–
MILLIMETERS
INCHES
8 PL
DIM
A
B
C
D
MIN
9.80
3.80
1.35
0.35
0.40
MAX
10.00
4.00
1.75
0.49
MIN
MAX
0.393
0.157
0.068
0.019
0.049
0.386
0.150
0.054
0.014
0.016
R X 45°
G
F
1.25
G
J
K
M
P
R
1.27 BSC
0.050 BSC
–T
–
SEATING
PLANE
0.19
0.10
0.25
0.25
0.008
0.004
0.009
0.009
J
M
F
16 PL
D
K
5.80
0.25
6.20
0.50
0.229
0.010
0.244
0.019
M
S
B
S
A
0.25 (0.010)
T
Lansdale Semiconductor reserves the right to make changes without further notice to any products herein to improve reliabil-
ity, function or design. Lansdale does not assume any liability arising out of the application or use of any product or circuit
described herein; neither does it convey any license under its patent rights nor the rights of others. “Typical” parameters which
may be provided in Lansdale data sheets and/or specifications can vary in different applications, and actual performance may
vary over time. All operating parameters, including “Typicals” must be validated for each customer application by the cus-
tomer’s technical experts. Lansdale Semiconductor is a registered trademark of Lansdale Semiconductor, Inc.
Page 16 of 16
www.lansdale.com
Issue c
相关型号：
ML13FAD-FREQ-OUT21
CMOS Output Clock Oscillator, 0.000002MHz Min, 0.032768MHz Max, 0.032768MHz Nom, NICKEL HEADER, DIP-4
MTRONPTI
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