MT8965AC [MITEL]
Integrated PCM Filter Codec; 综合PCM编解码器过滤型号: | MT8965AC |
厂家: | MITEL NETWORKS CORPORATION |
描述: | Integrated PCM Filter Codec |
文件: | 总22页 (文件大小:327K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
ISO2-CMOS
MT8960/61/62/63/64/65/66/67
Integrated PCM Filter Codec
ISSUE 10
May 1995
Features
•
ST-BUS compatible
Ordering Information
•
Transmit/Receive filters & PCM Codec in one
I.C
MT8964/65AC
MT8960/61/64/65AE
MT8962/63AE
18 Pin Ceramic DIP
18 Pin Plastic DIP
20 Pin Plastic DIP
20 Pin SOIC
•
•
•
•
Meets AT&T D3/D4 and CCITT G711 and G712
µ-Law: MT8960/62/64/67
A-Law: MT8961/63/65/67
Low power consumption:
MT8962/63/66/67AS
0°C to+70°C
Op.: 30 mW typ.
Stby.: 2.5 mW typ.
Description
•
Digital Coding Options:
2
Manufactured in ISO -CMOS, these integrated filter/
codecs are designed to meet the demanding
performance needs of the digital telecommunications
industry, e.g., PABX, Central Office, Digital
telephones.
MT8964/65/66/67 CCITT Code
MT8960/61/62/63 Alternative Code
•
•
•
Digitally controlled gain adjust of both filters
Analog and digital loopback
Filters and codec independently user
accessible for testing
•
•
•
•
Powerdown mode available
2.048 MHz master clock input
Up to six uncommitted control outputs
±5V ±5% power supply
ANUL
Analog to
Digital PCM
Encoder
Output
Register
Transmit
Filter
V
DSTo
X
SD0
SD1
SD2
SD3
SD4
SD5
CSTi
CA
A Register
8-Bits
Output
Register
Control
Logic
F1i
C2i
B-Register
8-Bits
PCM Digital
to Analog
Decoder
Input
Register
Receive
Filter
DSTi
V
R
V
GNDA GNDD
V
V
EE
Ref
DD
Figure 1 - Functional Block Diagram
6-19
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
MT8962/63/66/67
MT8960/61/64/65
20
19
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
CSTi
DSTi
C2i
DSTo
VDD
SD5
SD4
F1i
GNDD
VRef
GNDA
VR
ANUL
VX
VEE
SD0
SD1
SD2
18
17
16
15
14
13
12
11
10
1
2
3
4
5
6
7
8
9
CSTi
DSTi
C2i
DSTo
VDD
F1i
CA
SD3
SD2
GNDD
VRef
GNDA
VR
ANUL
VX
VEE
SD0
SD1
CA
SD3
9
10
18 PIN CERDIP/PDIP
20 PIN PDIP/SOIC
Figure 2 - Pin Connections
Description
Pin Description
Pin Name
CSTi
Control ST-BUS In is a TTL-compatible digital input used to control the function of the filter/codec.
Three modes of operation may be effected by applying to this input a logic high (VDD), logic low
(GNDD), or an 8-bit serial word, depending on the logic states of CA and F1i.
Functions controlled are: powerdown, filter gain adjust, loopback, chip testing, SD outputs.
DSTi
C2i
Data ST-BUS In accepts the incoming 8-bit PCM word. Input is TTL-compatible.
Clock Input is a TTL-compatible 2.048 MHz clock.
DSTo Data ST-BUS Out is a three-state digital output driving the PCM bus with the outgoing 8-bit PCM
word.
VDD
F1i
Positive power Supply (+5V).
Synchronization Input is an active low digital input enabling (in conjunction with CA) the PCM input,
PCM output and digital control input. It is internally sampled on every positive edge of the clock, C2i,
and provides frame and channel synchronization.
CA
Control Address is a three-level digital input which enables PCM input and output and determines
into which control register (A or B) the serial data, presented to CSTi, is stored.
SD3
System Drive Output is an open drain output of an N-channel transistor which has its source tied to
GNDA. Inactive state is open circuit.
SD4-5 System Drive Outputs are open drain outputs of N-channel transistors which have their source tied
to GNDD. Inactive state is open circuit.
SD0-2 System Drive Outputs are “Totempole“ CMOS outputs switching between GNDD and V . Inactive
DD
state is logic low.
VEE
VX
Negative power supply (-5V).
Voice Transmit is the analog input to the transmit filter.
ANUL Auto Null is used to integrate an internal auto-null signal. A 0.1µF capacitor must be connected
between this pin and GNDA.
VR
GNDA Analog ground (0V).
Voice Receive is the analog output of the receive filter.
VRef
Voltage Reference input to D to A converter.
GNDD Digital ground (0V).
6-20
ISO2-CMOS MT8960/61/62/63/64/65/66/67
MT8960/62
MT8964/66
Digital Output
Digital Output
11111111
11110000
11100000
11010000
11000000
10110000
10100000
10010000
10000000
10001111
10011111
10101111
10111111
11001111
11011111
11101111
10000000
00000000
00010000
11111111
01111111
01101111
00100000
00110000
01000000
01010000
01100000
01110000
01111111
01011111
01001111
00111111
00101111
00011111
00001111
00000000
-2.415V -1.207V
0V
+1.207V +2.415V
Analog Input Voltage (V
)
Bit 7...
MSB
0
IN
LSB
Figure 3 - µ-Law Encoder Transfer Characteristic
MT8961/63
MT8965/67
Digital Output
Digital Output
11111111
11110000
11100000
11010000
11000000
10110000
10100000
10101010
10100101
10110101
10000101
10010101
11100101
11110101
10010000
10000000
00000000
00010000
11000101
11010101
01010101
01000101
00100000
00110000
01000000
01010000
01100000
01110000
01111111
01110101
01100101
00010101
00000101
00110101
00100101
00101010
-2.5V
-1.25V
0V
+2.5V
+1.25V
Analog Input Voltage (V
)
Bit 7...
MSB
0
IN
LSB
Figure 4 - A-Law Encoder Transfer Characteristic
6-21
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
are 30 dB for 0-60 Hz and 35 dB for 4.6 kHz and
above.
Functional Description
Figure 1 shows the functional block diagram of the
MT8960-67. These devices provide the conversion
interface between the voiceband analog signals of a
telephone subscriber loop and the digital signals
required in a digital PCM (pulse code modulation)
switching system. Analog (voiceband) signals in the
The filter output signal is an 8 kHz staircase
waveform which is fed into the codec capacitor array,
or alternatively, into an external capacitive load of
250 pF when the chip is in the test mode. The digital
encoder generates an eight-bit digital word
representation of the 8 kHz sampled analog signal.
The first bit of serial data stream is bit 7 (MSB) and
represents the sign of the analog signal. Bits 4-6
represent the chord which contains the analog
sample value. Bits 0-3 represent the step value of
the analog sample within the selected chord. The
MT8960-63 provide a sign plus magnitude PCM
output code format. The MT8964/66 PCM output
code conforms to the AT &T D3 specification, i.e.,
true sign bit and inverted magnitude bits. The
MT8965/67 PCM output code conforms to the CCITT
specifications with alternate digit inversion (even bits
inverted). See Figs. 3 and 4 for the digital output
transmit path enter the chip at V , are sampled at
X
8kHz, and the samples quantized and assigned 8-bit
digital values defined by logarithmic PCM encoding
laws. Analog signals in the receive path leave the
chip at V after reconstruction from digital 8-bit
R
words.
Separate switched capacitor filter sections are used
for bandlimiting prior to digital encoding in the
transmit path and after digital decoding in the receive
path. All filter clocks are derived from the 2.048 MHz
master clock input, C2i. Chip size is minimized by
the use of common circuitry performing the A to D
and D to A conversion. A successive approximation
technique is used with capacitor arrays to define the
16 steps and 8 chords in the signal conversion
process. Eight-bit PCM encoded digital data enters
and leaves the chip serially on DSTi and DSTo pins,
respectively.
code corresponding to the analog voltage, V , at V
IN
X
input.
The eight-bit digital word is output at DSTo at a
nominal rate of 2.048 MHz, via the output buffer as
the first 8-bits of the 125 µs sampling frame.
Receive Path
Transmit Path
An eight-bit PCM encoded digital word is received on
DSTi input once during the 125 µs period and is
loaded into the input register. A charge proportional
to the received PCM word appears on the capacitor
array and an 8 kHz sample and hold circuit
integrates this charge and holds it for the rest of the
sampling period.
Analog signals at the input (Vx) are firstly
bandlimited to 508 kHz by an RC lowpass filter
section. This performs the necessary anti-aliasing
for the following first-order sampled data lowpass
pre-filter which is clocked at 512 kHz. This further
bandlimits the signal to 124 kHz before a fifth-order
elliptic lowpass filter, clocked at 128 kHz, provides
the 3.4 kHz bandwidth required by the encoder
section. A 50/60 Hz third-order highpass notch filter
clocked at 8 kHz completes the transmit filter path.
Accumulated DC offset is cancelled in this last
section by a switched-capacitor auto-zero loop which
integrates the sign bit of the encoded PCM word, fed
back from the codec and injects this voltage level
into the non-inverting input of the comparator. An
integrating capacitor (of value between 0.1 and 1 µF)
must be externally connected from this point (ANUL)
to the Analog Ground (GNDA).
The receive (D/A) filter provides interpolation filtering
on the 8 kHz sample and hold signal from the codec.
The filter consists of a 3.4 kHz lowpass fifth-order
elliptic section clocked at 128 kHz and performs
bandlimiting and smoothing of the 8 kHz "staircase"
waveform. In addition, sinx/x gain correction is
applied to the signal to compensate for the
attenuation of higher frequencies caused by the
capacitive sample and hold circuit. The absolute
gain of the receive filter can be adjusted from 0 dB to
-7 dB in 1 dB steps by means of three binary
controlled gain pads.
characteristics, with the limits shown in Figure 11,
meet the CCITT and AT
specifications.
The resulting lowpass
The absolute gain of the transmit filter (nominally 0
dB at 1 kHz) can be adjusted from 0 dB to 7 dB in 1
dB steps by means of three binary controlled gain
pads.
& T recommended
Typical attenuation at 4.6 kHz and above is 30 dB.
The filter is followed by a buffer amplifier which
will drive 5V peak/peak into a 10k ohm load, suitable
for driving electronic 2-4 wire circuits.
The resulting bandpass characteristics with the limits
shown in Figure 10 meet the CCITT and AT&T
recommended specifications. Typical atttenuations
6-22
ISO2-CMOS MT8960/61/62/63/64/65/66/67
driving a large number of codecs due to the high
V
Ref
input impedance of the VRef input.
Normal
precautions should be taken in PCB layout design to
minimize noise coupling to this pin. A 0.1 µF
capacitor connected from VRef to ground and located
as close as possible to the codec is recommended to
minimize noise entering through VRef. This capacitor
should have good high frequency characteristics.
An external voltage must be supplied to the VRef pin
which provides the reference voltage for the digital
encoding and decoding of the analog signal. For
VRef = 2.5V, the digital encode decision value for
overload (maximum analog signal detect level) is
equal to an analog input VIN = 2.415V (µ-Law
version) or 2.5V (A-Law version) and is equivalent to
a
signal level of 3.17 dBm0 or 3.14 dBm0
Timing
respectively, at the codec.
The codec operates in a synchronous manner (see
Figure 9a). The codec is activated on the first
positive edge of C2i after F1i has gone low. The
digital output at DSTo (which is a three-state output
driver) will then change from a high impedance state
to the sign bit of the encoded PCM word to be
output. This will remain valid until the next positive
edge, when the next most significant bit will be
output.
The analog output voltage from the decoder at V is
defined as:
R
µ-Law:
C
-0.5
2
16.5 + S
V
X
V
±
+
[( 128 ) (128 )( 33 )]
Ref
OFFSET
A-Law:
C+1
2
0.5 + S
V
X
V
±
[(128 )( 32 )] OFFSETC=0
Ref
Ref
On the first negative clock edge (after F1i signal has
been internally synchronized and CA is at GNDD or
VEE) the logic signal present at DSTi will be clocked
into the input shift register as the sign bit of the
incoming PCM word.
C
2
16.5 + S
V
X
V
±
[(128 )( 32 )] OFFSETC≠0
where C = chord number (0-7)
The eight-bit word is thus input at DSTi on negative
edges of C2i and output at DSTo on positive edges
of C2i.
S = step number (0-15)
VRef is a high impedance input with a varying
capacitive load of up to 40 pF.
F1i must return to a high level after the eighth
clock pulse causing DSTo to enter high impedance
and preventing further input data to DSTi. F1i will
continue to be sampled on every positive edge of
C2i. (Note: F1i may subsequently be taken low
during the same sampling frame to enable entry of
serial data into CSTi. This occurs usually mid-frame,
in conjunction with CA=VDD, in order to enter an 8-bit
control word into Register B. In this case, PCM input
and output are inhibited by CA at VDD.)
The recommended reference voltage for the MT8960
series of codecs is 2.5V ±0.5%. The output voltage
from the reference source should have a maximum
temperature coefficient of 100 ppm/C°. This voltage
should have a total regulation tolerance of ±0.5%
both for changes in the input voltage and output
loading of the voltage reference source. A voltage
reference circuit capable of meeting these
specifications is shown in Figure 5. Analog Devices
’AD1403A voltage reference circuit is capable of
NC
8
NC
7
NC
6
NC
5
V
Ref
0.1 µF
AD1403A
MT8960-67
FILTER/CODEC
1
2
3
4
NC
+5V
2.5V
Figure 5 - Typical Voltage Reference Circuit
6-23
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
Internally the codec will then perform a decode cycle
on the newly input PCM word. The sampled and
held analog signal thus decoded will be updated 25
µs from the start of the cycle. After this the analog
input from the filter is sampled for 18 µs, after which
digital conversion takes place during the remaining
82 µs of the sampling cycle.
Mode 2
CA= -5V (VEE); CSTi receives an eight-bit control
word
CSTi accepts a serial data stream synchronously
with DSTi (i.e., it accepts an eight-bit serial word in a
3.9 µs timeslot, updated every 125 µs, and is
specified
considerations).
entered into Control Register
programming of the following functions: transmit and
receive gain, powerdown, loopback. Register B is
reset to zero and the SD outputs assume their
inactive state. Test modes cannot be entered.
Since a single clock frequency of 2.048 MHz is
required, all digital data is input and output at this
rate. DSTo, therefore, assumes a high impedance
state for all but 3.9 µs of the 125 µs frame. Similarly,
DSTi input data is valid for only 3.9 µs.
identically
This eight-bit control word is
and enables
to
DSTi
for
timing
A
Digital Control Functions
CSTi is a digital input (levels GNDD to V ) which is
Mode 3
DD
used to control the function of the filter/codec. It
operates in three different modes depending on the
logic levels applied to the Control Address input
(CA) and chip enable input (F1i) (see Table 1).
CA=0V (GNDD); CSTi receives an eight-bit control
word
As in Mode 2, the control word enters Register A and
the aforementioned functions are controlled. In this
mode, however, Register B is not reset, thus not
affecting the states of the SD outputs.
Mode 1
CA=-5V (VEE); CSTi=0V (GNDD)
The filter/codec is in normal operation with nominal
transmit and receive gain of 0dB. The SD outputs
are in their active states and the test modes cannot
be entered.
CA=+5V (VDD); CSTi receives an 8-bit control word
In this case the control word is transferred into
Register B. Register A is unaffected. The input and
output of PCM data is inhibited.
CA = -5V (VEE); CSTi = +5V (VDD
)
The contents of Register
B controls the six
A state of powerdown is forced upon the chip
whereby DSTo becomes high impedance, VR is
connected to GNDA and all analog sections have
power removed.
uncommitted outputs SD0-SD5 (four outputs, SD0-
SD3, on MT8960/61/64/65 versions of chip) and also
provide entry into one of the three test modes of the
chip.
MODE
CA
CSTi
FUNCTION
1
VEE
GNDD
VDD
Normal chip operation.
(Note 1)
Powerdown.
2
VEE
GNDD
VDD
Serial
Data
Eight-bit control word into Register A. Register B is reset.
3
Serial
Data
Eight-bit control word into register A. Register B is unaffected.
Eight-bit control word into register A. Register B is unaffected.
(Note 2)
Serial
Data
Note 1:
Note 2:
When operating in Mode 1, there should be only one frame pulse (F1i) per 125µs frame
When operating in Mode 3, PCM input and output is inhibited by CA=VDD
.
Table 1. Digital Control Modes
6-24
ISO2-CMOS MT8960/61/62/63/64/65/66/67
Note: For Modes 1 and 2, F1i must be at logic low
for one period of 3.9 µs, in each 125 µs cycle, when
PCM data is being input and output, and the control
word at CSTi enters Register A. For Mode 3, F1i
must be at a logic low for two periods of 3.9 µs, in
each 125 µs cycle. In the first period, CA must be at
GNDD or VEE, and in the second period CA must be
TRANSMIT (A/D)
FILTER GAIN (dB)
BIT 2
BIT 1
BIT 0
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
+ 1
+ 2
+ 3
+ 4
+ 5
+ 6
+ 7
high (VDD)
.
Control Registers A, B
The contents of these registers control the filter/
codec functions as described in Tables 2 and 3.
Bit 7 of the registers is the MSB and is defined as the
first bit of the serial data stream input (corresponding
to the sign bit of the PCM word).
RECEIVE (D/A)
FILTER GAIN (dB)
BIT 5
BIT 4
BIT 3
On initial power-up these registers are set to the
powerdown condition for a maximum of 25 clock
cycles. During this time it is impossible to change
the data in these registers.
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
- 1
- 2
- 3
- 4
- 5
- 6
- 7
Chip Testing
By enabling Register B with valid data (eight-bit
control word input to CSTi when F1i=GNDD and CA=
VCC) the chip testing mode can be entered. Bits 6
and 7 (most sign bits) define states for testing the
transmit filter, receive filter and the codec function.
The input in each case is VX input and the output in
each case is VR output. (See Table 3 for details.)
BIT 7
BIT 6
FUNCTION CONTROL
0
0
1
1
0
1
0
1
Normal operation
Digital Loopback
Analog Loopback
Powerdown
Loopback
Loopback of the filter/codec is controlled by the
control word entered into Register A. Bits 6 and 7
(most sign bits) provide either a digital or analog
loopback condition. Digital loopback is defined as
follows:
Table 2. Control States - Register A
•
PCM input data at DSTi is latched into the PCM
input register and the output of this register is
connected to the input of the 3-state PCM
output register.
•
Analog output buffer at VR has its input shorted
to GNDA and disconnected from the receive
filter output.
•
•
Analog input at VX is disconnected from the
transmit filter input.
•
•
The digital input to the PCM digital-to-analog
decoder is disconnected, forced to zero (0).
The receive filter output is connected to the
transmit filter input. Thus the decode signal is
fed back through the receive path and encoded
in the normal way. The analog output buffer at
The output of the PCM encoder is disabled and
thus the encoded data is lost. The PCM output
at DSTo is determined by the PCM input data.
V is not tested by this configuration.
R
Analog loopback is defined as follows:
•
PCM input data is latched, decoded and filtered
as normal but not output at VR.
In both cases of loopback, DSTi is the input
and DSTo is the output.
6-25
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
Logic Control Outputs SD0-5
These outputs are directly controlled by the logic
states of bits 0-5 in Register B. A logic low (GNDD)
in Register B causes the SD outputs to assume an
inactive state. A logic high (VDD) in Register B
causes the SD outputs to assume an active state
(see Table 3). SD0-2 switch between GNDD and VDD
Telephone Set
2 Wire
Analog
and may be used to control external logic or
transistor circuitry, for example, that employed on the
line card for performing such functions as relay drive
PCM Highway
Supervision
for application of ringing to line, message waiting
Protection
indication, etc.
MT8960/61
MT8962/63
MT8964/65
MT8966/67
Battery
Feed
2W/4W
Converter
SD3-5 are used primarily to drive external analog
Ringing
circuitry. Examples may include the switching in or
out of gain sections or filter sections (eg., ring trip
filter) (Figure 7).
MT8962/63/66/67 provides all six SD outputs.
MT8960/61/64/65 each packaged in an 18-pin DIP
provide only four control outputs, SD0-3.
Figure 6 - Typical Line Termination
BITS 0-2
LOGIC CONTROL OUTPUTS SD0-SD2
Inactive state - logic low (GNDD).
0
1
Active state - logic high (V ).
DD
BIT 3
LOGIC CONTROL OUTPUT SD
3
0
1
Inactive state - High Impedance.
Active state - GNDA.
BITS 4,5
LOGIC CONTROL OUTPUTS SD , SD
4 5
0
1
Inactive state - High Impedance.
Active state - GNDD.
BIT 7 BIT 6
CHIP TESTING CONTROLS
0
0
0
1
Normal operation.
Transmit filter testing, i.e.:
Transmit filter input connected to VX input
Receive filter and Buffer disconnected from VR
1
1
0
1
Receive filter testing, i.e.:
Receive filter input connected to VX input
Receive filter input disconnected from codec
Codec testing i.e.:
Codec analog input connected to VX
Codec analog input disconnected from transmit filter output
Codec analog output connected to VR
VR disconnected from receive filter output
Table 3. Control States - Register B
6-26
ISO2-CMOS MT8960/61/62/63/64/65/66/67
External Control:
Powerdown
1)
Register A. Powerdown is controlled by bits 6
and 7 ( when both at logic high) of Register A
which in turn receives its control word input
via CSTi, when F1i is low and CA input is
either at VEE or GNDD. Power is removed
from the filters and analog sections of the chip.
The analog ouput buffer at VR will be
connected to GNDA. DSTo becomes high
impedance and the clocks to the majority of the
logic are stopped. SD outputs are unaffected
and may be updated as normal.
Powerdown of the chip is achieved in several ways:
Internal Control:
1)
Initial Power-up. Initial application of VDD and
EE causes powerdown for a period of 25 clock
V
cycles and during this period the chip will
accept input only from C2i. The B-register is
reset to zero forcing SD0-5 to be inactive. Bits
0-5 of Register A (gain adjust bits) are forced
to zero and bits 6 and 7 of Register A become
logic high thus reinforcing the powerdown.
2)
CSTi Input. With CA at VEE and CSTi held at
continuous logic high the chip assumes the
same state as described in External Control
(1) above.
2)
Loss of C2i. Powerdown is entered 10 to 40
µs after C2i has assumed a continuous logic
high (VDD). In this condition the chip will be in
the same state as in (1) above.
Note: If C2i stops at a continuous logic low
(GNDD), the digital data and status is
indeterminate.
Message
Waiting
-100V DC
MT8960/61/64/65
(With Relay
Drive)
From ST-BUS
From ST-BUS
Master Clock
to ST-BUS
5V
CSTi
DSTi
C2i
GNDD
V
2.5V
-5V
Ref
GNDA
DSTo
V
R
2/4 Wire
Converter
Telephone
Line
0.1µF
Ring Trip
Filter
(With Relay
Drive)
V
ANUL
DD
Gain
Section
Alignment
F1i
V
X
Register Select
CA
V
EE
SD3
SD2
SD0
SD1
Ring Feed
-48V DC
-48V DC
(With Relay
Drive)
90V
RMS
Figure 7 - Typical Use of the Special Drive Outputs
6-27
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
DSTi
DSTo
CDTi
V
V
X
Line
Interface
&
Monitoring
Circuitry
R
SD0
.
.
.
•
•
•
SDn
Line 1
Speech
Switch
-
MT8960-67
8980
8
8
•
•
•
•
•
•
Repeated for Lines
2 to 255
Repeated for Lines
2 to 255
Controlling
Micro-
Processor
8
8
Control &
Signalling
-
8980
DSTi
DSTo
CDTi
V
X
Line
Interface
&
Monitoring
Circuitry
V
R
SD0
.
.
.
•
•
•
SDn
Line 256
MT8960-67
Figure 8 - Example Architecture of a Simple Digital Switching System Using the MT8960-67
6-28
ISO2-CMOS MT8960/61/62/63/64/65/66/67
Absolute Maximum Ratings*
Parameter
Symbol
Min
Max
Units
1
DC Supply Voltages
VDD-GNDD
VEE-GNDD
VRef
-0.3
-6.0
+6.0
+0.3
VDD
V
V
2
3
4
Reference Voltage
Analog Input
GNDA
V
VX
VEE
VDD
V
Digital Inputs
Except CA
CA
GNDD-0.3
VEE-0.3
GNDD-0.3
VEE-0.3
VEE-0.3
V
DD+0.3
V
VDD+0.3
VDD+0.3
VDD+0.3
VDD+0.3
20
V
5
Output Voltage
SD0-2
SD3
V
V
SD4-5
V
6
7
8
Current On Any Pin
I
mA
°C
mW
I
Storage Temperature
TS
-55
+125
Power Dissipation at 25°C (Derate 16 mW/°C above 75°C)
PDiss
500
* Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied.
Recommended Operating Conditions - Voltages are with respect to GNDD unless otherwise stated
Characteristics
Supply Voltage
Sym
Min
Typ*
Max
Units
Comments
1
2
VDD
VEE
4.75
5.0
-5.0
2.5
0.0
0.0
5.25
V
V
-5.25
-4.75
VRef
V
See Note 1
Ref. to GNDA
VGNDD
Voltage On Digital Ground
Operating Temperature
-0.1
-0.4
+0.1
+0.4
Vdc
Vac
Ref. to GNDA 400ns max.
duration in 125µs cycle
3
4
TO
0
+70
°C
Operating Current
VDD
VEE
IDD
IEE
3.0
3.0
4.0
4.0
mA
mA
All digital inputs at VDD
or GNDD (or VEE for CA)
VRef
IRef
2.0
µA
Mean current
5
Standby Current
VDD
VEE
IDDO
IEEO
0.25
0.25
1.0
1.0
mA
mA
All digital inputs at VDD
or GNDD (or VEE for CA)
Note 1: Temperature coefficient of VRef should be better than 100 ppm/°C.
DC Electrical Characteristics - Voltages are with respect to GNDD unless otherwise stated.
T =0 to 70°C, V =5V±5%, V =-5V±5%, V =2.5V±0.5%, GNDA=GNDD=0V,Clock Frequency =2.048MHz. Outputs unloaded unless
A
DD
EE
Ref
otherwise specified.
Characteristics
Sym
Min
Typ*
Max
Units
Test Conditions
1
2
Input Current
Except CA
CA
II
10.0
10.0
0.8
µA
µA
V
VIN = GNDD to VDD
VIN = VEE to VDD
IIC
D
I
Input Low
Except CA
CA
VIL
VILC
0.0
VEE
2.4
0.0
V
+1.2
G Voltage
I
V
EE
3
4
Input High Voltage All Inputs
V
5.0
V
IH
T
A
L
Input Intermediate CA
Voltage
VIIC
0.8
V
5
Output Leakage
Current (Tristate) SD3-5
DSTo
I0Z
±0.1
µA
µA
Output High Impedance
10.0
* Typical figures are at 25°C with nominal ±5V supplies. For design aid only: not guaranteed and not subject to production testing.
6-29
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
DC Electrical Characteristics (cont’d)
Characteristics
Output Low
Sym
Min
Typ*
Max
Units
Test Conditions
IOUT =1.6 mA
6
7
DSTo
SD0-2
DSTo
SD0-2
SD3-5
VOL
VOL
VOH
VOH
ROUT
COUT
IIN
0.4
1.0
V
V
D
I
G
I
T
A
L
Voltage
IOUT =1 mA
Output High
Voltage
4.0
4.0
V
IOUT =-100µA
IOUT =-1mA
V
8
Output Resistance
1.0
4.0
2.0
KΩ
pF
µA
MΩ
pF
mV
Ω
VOUT =+1V
9
Output Capacitance DSTo
Output High Impedance
10
11
12
13
14
15
Input Current
VX
VX
VX
10.0
VEE ≤ VIN ≤ VCC
A
N
A
L
O
G
Input Resistance
Input Capacitance
RIN
10.0
30.0
+1.0
C
fIN = 0 - 4 kHz
See Note 2
IN
Input Offset Voltage VX
Output Resistance VR
Output Offset Voltage VR
VOSIN
ROUT
100
100
VOSOUT
mV
Digital Input= +0
Note 2: VOSIN specifies the DC component of the digitally encoded PCM word.
AC Electrical Characteristics - Voltages are with respect to GNDD unless otherwise stated.
TA=0 to 70°C, VDD=5V±5%, VEE=-5V±5%, VRef=2.5V±0.5%, GNDA=GNDD=0V, Clock Frequency=2.048 MHz. Outputs unloaded unless
otherwise specified.
Characteristics
Clock Frequency
Sym
Min
Typ*
Max
Units
Test Conditions
1
2
C2i
C2i
C2i
C2i
fC
2.046 2.048
2.05
50
MHz
ns
ns
%
See Note 3
Clock Rise Time
Clock Fall Time
Clock Duty Cycle
tCR
tCF
3
50
4
40
50
60
5
Chip Enable Rise Time F1i
Chip Enable Fall Time F1i
Chip Enable Setup Time F1i
Chip Enable Hold Time F1i
tER
tEF
tES
tEH
tOR
tOF
100
100
ns
ns
ns
ns
ns
ns
6
7
50
25
See Note 4
See Note 4
8
D
I
9
Output Rise Time
Output Fall Time
DSTo
DSTo
100
100
G
I
10
11
Propagation Delay Clock DSTo
to Output Enable
tPZL
tPZH
122
122
ns
ns
T
A
L
RL=10KΩ to VCC
12
13
14
15
16
Propagation Delay
Clock to Output
DSTo
tPLH
tPHL
100
100
ns
ns
C =100 pF
L
Input Rise Time
Input Fall Time
Input Setup Time
Input Hold Time
CSTi
DSTi
tIR
100
100
ns
ns
CSTi
DSTi
tIF
100
100
ns
ns
CSTi
DSTi
tISH
tISL
25
0
ns
ns
CSTi
DSTi
tIH
60
60
ns
ns
* Typical figures are at 25°C with nominal ±5V supplies. For design aid only: not guaranteed and not subject to production testing.
6-30
ISO2-CMOS MT8960/61/62/63/64/65/66/67
AC Electrical Characteristics (cont’d)
Characteristics
Sym
Min
Typ*
Max
Units
Test Conditions
CL = 100 pF
17
Propagation Delay
SD
tPCS
400
ns
D
I
Clock to SD Output
SD Output Fall Time
SD Output Rise Time
G
I
T
A
L
18
19
20
SD
SD
tSF
tSR
tDL
200
400
122
ns
ns
ns
CL = 20 pF
Digital Loopback
Time DSTi to DSTo
(See Figures 9a, 9b, 9c)
Note 3:
The filter characteristics are totally dependent upon the accuracy of the clock frequency providing F1i is synchronized to
C2i. The A/D and D/A functions are unaffected by changes in clock frequency.
Note 4:
This gives a 75 ns period, 50 ns before and 25 ns after the 50% point of C2i rising edge, when change in F1i will give an
undetermined state to to the internally synchronized enable signal.
AC Electrical Characteristics - Transmit (A/D) Path - Voltages are with respect to GNDD unless otherwise stated.
TA=0 to 70°C, VDD=5V±5%, VEE=-5V±5%, VRef=2.5V±0.5%, GNDA=GNDD=0V, Clock Frequency = 2.048MHz,
Filter Gain Setting = 0dB. Outputs unloaded unless otherwise specified.
Characteristics
Sym
Min
Typ*
Max
Units
Test Conditions
1
Analog Input at VX equivalent to
the overload decision level at
the codec
V
Level at codec:
µ-Law: 3.17 dBm0
A-Law: 3.14 dBm0
See Note 6
IN
4.829
5.000
VPP
VPP
2
3
Absolute Gain (0dB setting)
GAX
-0.25
-0.35
+0.25
+0.35
dB
dB
0 dBm0 @ 1004 Hz
Absolute Gain (+1dB to +7dB
settings)
from nominal,
@ 1004 Hz
4
5
Gain Variation
With Temp
GAXT
0.01
0.04
dB
T =0°C to 70°C
A
With Supplies
G
dB/V
AXS
A
N
A
L
O
G
Gain Tracking
(See Figure 12) CCITT G712
(Method 1)
GTX1
Sinusoidal Level:
+3 to -20 dBm0
Noise Signal Level:
-10 to -55 dBm0
-55 to -60 dBm0
-0.25
+0.25
dB
-0.25
-0.50
+0.25
+0.50
dB
dB
CCITT G712
(Method 2)
AT&T
GTX2
Sinusoidal Level:
+3 to -40 dBm0
-40 to -50 dBm0
-50 to -55 dBm0
-0.25
-0.50
-1.50
+0.25
+0.50
+1.50
dB
dB
dB
6
Quantization
Distortion
(See Figure 13) CCITT G712
(Method 1)
DQX1
Noise Signal Level:
-3 dBm0
-6 to -27 dBm0
-34 dBm0
-40 dBm0
-55 dBm0
28.00
35.60
33.90
29.30
14.20
dB
dB
dB
dB
dB
* Typical figures are at 25°C with nominal ±5V supplies. For design aid only: not guaranteed and not subject to production testing.
6-31
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
Transmit (A/D) Path (cont’d)
Characteristics
Sym
Min Typ* Max
Units
Test Conditions
Quantization
Distortion
(cont’d)
(See Figure 13)
CCITT G712
(Method 2)
AT&T
DQX2
Sinusoidal Input Level:
0 to -30 dBm0
-40 dBm0
35.30
29.30
24.30
dB
dB
dB
-45 dBm0
7
Idle Channel
Noise
C-message
N
N
18
-67
-56
-46
dBrnC0 µ-Law Only
dBm0p CCITT G712
dBm0 CCITT G712
CX
Psophometric
PX
8
9
Single Frequency Noise
NSFX
Harmonic Distortion
dB
Input Signal:
(2nd or 3rd Harmonic)
0 dBm0 @ 1.02 kHz
10
11
Envelope Delay
DAX
DDX
270
µs
@ 1004 Hz
Envelope Delay 1000-2600 Hz
Variation With
Frequency
60
150
250
µs
µs
µs
Input Signal:
400-3200 Hz Sinewave
at 0 dBm0
600-3000 Hz
400-3200 Hz
12
Intermodulation CCITT G712
IMDX1
IMDX2
-55
-41
dB
50/60 Hz @ -23 dBm0
and any signal within
300-3400 Hz at -9 dBm0
Distortion
50/60 Hz
A
N
A
L
O
G
CCITT G712
2 tone
dB
740 Hz and 1255 Hz
@ -4 to -21 dBm0.
Equal Input Levels
AT&T
IMDX3
IMDX4
GRX
-47
-49
dB
dB
2nd order products
3rd order products
0 dBm0 Input Signal
4 tone
13
Gain Relative to ≤50 Hz
Gain @ 1004 Hz 60 Hz
(See Figure 10) 200 Hz
-25
-30
dB
dB
dB
dB
dB
dB
dB
dB
dB
-1.8
0.00
0.125
0.125
0.030
-0.100
-14
Transmit
Filter
Response
300-3000 Hz
-0.125
-0.275
-0.350
-0.80
3200 Hz
3300 Hz
3400 Hz
4000 Hz
≥4600 Hz
-32
14
15
16
Crosstalk D/A to A/D
CTRT
-70
dB
0 dBm0 @ 1.02 kHz
in D/A
Power Supply
Rejection
VDD
VEE
PSSR1
PSSR
33
35
dB
dB
Input 50 mVRMS at
1.02 kHz
2
Overload Distortion (See Fig.15)
Input frequency=1.02kHz
* Typical figures are at 25°C with nominal ±5V supplies. For design aid only: not guaranteed and not subject to production testing.
Note 6:
0dBm0=1.185 VRMS for the µ-Law codec.
0dBm0=1.231 VRMS for the A-Law codec.
6-32
ISO2-CMOS MT8960/61/62/63/64/65/66/67
AC Electrical Characteristics - Receive (D/A) Path - Voltages are with respect to GNDD unless otherwise stated.
TA=0 to 70°C, VDD=5V±5%, VEE=-5V±5%, VRef=2.5V±0.5%, GNDA=GNDD=0V, Clock Frequency = 2.048MHz,
Filter Gain Setting = 0dB. Outputs unloaded unless otherwise specified.
Characteristics
Analog output at VR
equivalent to the overload
decision level at codec
Sym
Min
Typ*
Max
Units
Test Conditions
1
VOUT
Level at codec:
µ-Law: 3.17 dBm0
A-Law: 3.14 dBm0
RL=10 KΩ
4.829
5.000
Vpp
Vpp
See Note 7
2
3
Absolute Gain (0dB setting)
GAR
-0.25
-0.35
+0.25
+0.35
dB
dB
0 dBm0 @ 1004Hz
Absolute Attenuation (-1dB
to -7dB settings)
From nominal,
@ 1004Hz
4
5
Gain Variation
With Temp.
GART
GARS
GTR1
0.01
0.04
dB
TA=0°C to 70°C
With Supplies
CCITT G712
dB/V
Gain Tracking
(See Figure 12) (Method 1)
Sinusoidal Level:
+3 to -10 dBm0
Noise Signal Level:
-10 to -55 dBm0
-55 to -60 dBm0
-0.25
+0.25
dB
-0.25
-0.50
+0.25
+0.50
dB
dB
CCITT G712
(Method 2)
AT & T
GTR2
Sinusoidal Level:
+3 to -40 dBm0
-40 to -50 dBm0
-50 to -55 dBm0
-0.25
-0.50
-1.50
+0.25
+0.50
+1.50
dB
dB
dB
A
N
A
L
O
G
6
Quantization
Distortion
(See Fig. 13)
CCITT G712
(Method 1)
DQR1
Noise Signal Level:
-3 dBm0
-6 to -27 dBm0
-34 dBm0
-40 dBm0
-55 dBm0
28.00
35.60
33.90
29.30
14.30
dB
dB
dB
dB
dB
DQR2
Sinusoidal Input Level:
0 to -30 dBm0
-40 dBm0
CCITT G712
(Method 2)
AT & T
36.40
30.40
25.40
dB
dB
dB
-45 dBm0
7
Idle Channel
Noise
C-message
NCR
NPR
12
-75
-56
-46
dBrnC0 µ-Law Only
dBm0p CCITT G712
dBm0 CCITT G712
Psophometric
8
9
Single Frequency Noise
NSFR
Harmonic Distortion
dB
Input Signal 0 dBm0
(2nd or 3rd Harmonic)
at 1.02 kHz
10
Intermodulation CCITT G712
IMDR2
-41
dB
Distortion
2 tone
AT & T
4 tone
IMDR3
IMDR4
-47
-49
dB
dB
2nd order products
3rd order products
* Typical figures are at 25°C with nominal ±5V supplies. For design aid only: not guaranteed and not subject to production testing.
6-33
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
Receive (D/A) Path (cont’d)
Characteristics
Envelope Delay
Envelope Delay 1000-2600 Hz
Sym
Min
Typ*
Max
Units
Test Conditions
@ 1004 Hz
11
12
DAR
DDR
210
µs
90
170
265
µs
µs
µs
Input Signal:
400 - 3200 Hz digital
sinewave at 0 dBm0
Variation with
Frequency
600-3000 Hz
400-3200 Hz
13
Gain Relative to <200 Hz
Gain @ 1004 Hz 200 Hz
GRR
0.125
0.125
0.125
0.030
-0.100
-14.0
-28.0
dB
dB
dB
dB
dB
dB
dB
0 dBm0 Input Signal
-0.5
A
N
A
L
O
G
(See Figure 11)
300-3000 Hz
-0.125
-0.350
-0.80
Receive
Filter
Response
3300 Hz
3400 Hz
4000 Hz
≥4600 Hz
14
15
16
Crosstalk A/D to D/A
CTTR
-70
dB
0 dBm0 @ 1.02 kHz
in A/D
Power Supply
Rejection
VDD
VEE
PSRR3
PSRR4
33
35
dB
dB
Input 50 mVRMS at
1.02 kHz
Overload Distortion
(See Fig. 15)
Input frequency=1.02 kHz
* Typical figures are at 25°C with nominal ±5V supplies. For design aid only: not guaranteed and not subject to production testing.
Note 7: 0dBm0=1.185 VRMS for µ-Law codec and 0dBm0=1.231 VRMS for A-Law codec.
125 µs
C2i
INPUT
F1i
INTERNAL
ENABLE
DSTo
OUTPUT
HIGH IMPEDANCE
7
7
6
6
5
5
4
4
3
3
2
2
1
1
0
0
7
7
DSTi
INPUT
6
5V
CA
(Mode 3)
0V
CSTi
INPUT
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
7
6
LOAD
A-REGISTER
LOAD
B-REGISTER
Figure 9a - Timing Diagram - 125µs Frame Period
6-34
ISO2-CMOS MT8960/61/62/63/64/65/66/67
8 CLOCK CYCLES
(See Note)
90%
50%
10%
C2i
Input
t
t
CF
CR
t
t
EF
ER
90%
10%
F1i
Input
t
t
t
t
t
t
EH
ES
EH
ES
EH
ES
DSTo
Output
high
impedance
high-Z
t
t
PZL
PZH
t
t
PZL
PZH
Figure 9b - Timing Diagram - Output Enable
Note:
In typical applications, F1i will remain low for 8 cycles of C2i. However, the device will function normally as long as t
EH
and
ES
t
are met at each positive edge of C2i.
90%
50%
10%
C2i
Input
t
t
CF
CR
90%
50%
10%
DSTo
Output
t
OR
t
OF
t
PLH
t
PLH
90%
50%
10%
DSTi, CSTi
Input
t
IF
t
IR
t
IH
t
ISL
t
ISH
Figure 9c - Timing Diagram - Input/Output
6-35
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
SCALE B
SCALE A
PASSBAND ATTENUATION
SCALE A SCALE B
-0.125
STOPBAND ATTENUATION
0
-0.125
0.35
0.125
0.35
∏(4000-F)
1200
SIN
-14
- 1
1
10
14
10
1
∏(4000-F)
-18 SIN
Attenuation
Relative To
Attenuation
At 1 kHz (dB)
-7/9
1200
20
Note: Above function
crossover occurs
at 4000Hz.
20
25
30
2
2
3
4
30
32
3
4
40
40
0
5060 100
200
300
3000
3200 3300 3400
4000
4600
5000
10000
FREQUENCY (Hz)
Figure 10 - Attenuation vs Frequency for Transmit (A/D) Filter
SCALE A
-0.125
SCALE B
SCALE A
PASSBAND ATTENUATION
STOPBAND ATTENUATION
0
1
0.125
0.35
∏(4000-F)
1200
SIN
-14
- 1
10
14
1
2
3
4
Attenuation
Relative To
Attenuation
At 1 kHz (dB)
20
2
3
4
28
30
40
0
100
200
300
3000
3200 3300 3400
4000
4600
5000
10000
FREQUENCY (Hz)
Figure 11 - Attenuation vs Frequency for Receive (D/A) Filter
6-36
ISO2-CMOS MT8960/61/62/63/64/65/66/67
5a. CCITT Method 1
CCITT End-To-End Spec
+1.0
+1.0
+0.5
+0.25
0
+0.5
+0.25
0
1
2
Channel Spec
Input Level
(dBm0)
-60 -55 -50
-40
-30
-20
-10
-10
0 -3
-0.25
-0.5
-0.25
-0.5
-1.0
-1.0
Bandlimited White Noise Test Signal
Sinusiodal Test Signal
5b. CCITT Method 2
+1.5
+1.0
+0.5
CCITT End-To-End Spec
1
2
Channel Spec
+0.25
0
Input Level
(dBm0)
-60
-50
-40
-30
-20
-10
0 +3
-0.25
-0.5
-1.0
-1.5
Sinusoidal Test Signal
Figure 12 - Variation of Gain With Input Level
6-37
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
6a. CCITT Method 1
40
1
2
Channel Spec
35.6
33.9
33.9
30
20
10
0
32.2
29.3
28.0
27.6
26.3
CCITT End-To-End
Spec
14.3
12.6
-20
-10
-6
-3
0
+3
-60
-55
-50
-40
-34
-30 -27
Input Level (dBm0)
6b. CCITT Method 2
40
30
20
10
0
1
2
Channel Spec
D/A
Channel Spec
A/D
36.4
36.4
35.3
33.0
1
2
35.3
33.0
30.4
22.0
CCITT
29.3
27.0
End-To-End
Spec
25.4
24.3
-60
-50
-40
-30
-20
-10
0
Input Level (dBm0)
Figure 13 - Signal to Total Distortion Ratio vs Input Level
6-38
ISO2-CMOS MT8960/61/62/63/64/65/66/67
1000
750
CCITT
Channel Spec
½
(2800Hz)
500
370
250
125
0
(600Hz)
(2600Hz)
2500
500
1000
1500
2000
3000
Figure 14 - Envelope Delay Variation Frequency
5
4.5
4
3
3
4
5
6
7
8
9
Input Level (dBm0)
*Relative to Fundamental Output power level with +3dBm0 input signal level at a frequency of 1.02kHz.
Figure 15 - Overload Distortion (End-to-End)
6-39
MT8960/61/62/63/64/65/66/67 ISO2-CMOS
NOTES:
6-40
相关型号:
MT8966ASR1
PCM Codec, MU-Law, 1-Func, CMOS, PDSO20, 0.300 INCH, LEAD FREE, MS-013AC, SOIC-20
MICROSEMI
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