MAX562EWI+T [MAXIM]
Line Transceiver, 1 Func, 3 Driver, 5 Rcvr, CMOS, PDSO28, 0.300 INCH, SO-28;型号: | MAX562EWI+T |
厂家: | MAXIM INTEGRATED PRODUCTS |
描述: | Line Transceiver, 1 Func, 3 Driver, 5 Rcvr, CMOS, PDSO28, 0.300 INCH, SO-28 驱动 光电二极管 接口集成电路 驱动器 |
文件: | 总8页 (文件大小:84K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
19-0144; Rev. 0; 9/93
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
MAX562
_______________Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
♦ 230kbps Data Rate, LapLink™ Compatible
♦ Operates from a 2.7V to 5.25V Supply
♦ Designed for EIA/TIA-562 and EIA/TIA-232 Applications
♦ Guaranteed 4.0V/µs Slew Rate
The MAX562 is designed specifically for notebook and
palmtop computers that need to transfer data quickly.
It runs at data rates up to 230kbps, and has a guaran-
te e d 4V/µs s le w ra te . This d e vic e me e ts the ne w
EIA/TIA-562 standard that guarantees compatibility with
RS-232 interfaces.
♦ 3 Drivers, 5 Receivers
The MAX562 has low-power shutdown and keep-awake
modes. In keep-awake mode, the transmitters are dis-
abled but all receivers are active, allowing unidirection-
al communication. In shutdown mode, the entire chip is
disabled and all outputs are in a high-impedance state.
♦ Flow Through Pinout
♦ Low-Power Shutdown and Keep-Awake Modes
♦ Low-Cost, Surface-Mount External Capacitors
The MAX562 is available in a standard 28-pin SO pack-
a g e , a nd in a s ma lle r footp rint s hrink s ma ll-outline
package (SSOP).
______________Ord e rin g In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
28 SO
________________________Ap p lic a t io n s
MAX562CWI
MAX562CAI
MAX562C/D
MAX562EWI
MAX562EAI
Palmtop, Notebook, and Subnotebook
Computers
28 SSOP
Dice*
Peripherals
28 SO
Battery-Powered Equipment
28 SSOP
* Contact factory for dice specifications.
__________Typ ic a l Op e ra t in g Circ u it
0.33µF
0.33µF
__________________P in Co n fig u ra t io n
MAX562
2
C1A
5
3
C1B
4
+2.7V TO
+5.25V
C1A+ C1A-
V
CC
C1B+ C1B-
1
28
TOP VIEW
VOLTAGE
DOUBLER/TRIPLER
V+
0.33µF
C3
0.68µF
INPUT
25
V+
28
27
26
25
24
23
V
1
C2+
C2-
CC
VOLTAGE
INVERTER
26
C2
V-
24
0.33µF
T1
C1A+
C1B+
C1B-
C1A-
GND
V-
C4
0.33µF
2
11
18
17
3
T1
T2
T1
IN
OUT
C2+
C2-
4
EIA/TIA
-562
OUTPUTS
12
CMOS
INPUTS
T2
IN
T2
OUT
5
6
MAX562
R1
13
6
16
23
R1
IN
OUT
T3
T3
R1
T3
OUT
IN
R2
R3
R4
7
22 R2
21 R3
OUT
OUT
OUT
IN
IN
R1
OUT
R1
IN
5k
8
22
21
20
7
8
9
R2
R2
IN
R2
R3
R4
R5
9
20
OUT
R4
IN
5k
5k
5k
5k
EIA/TIA
-562
INPUTS
R5
10
IN 11
IN 12
19
R5
OUT
IN
R3
OUT
R3
IN
CMOS
OUTPUTS
T1
T2
T3
18 T1
OUT
OUT
R4
OUT
R4
IN
T2
T3
17
16
15
13
14
IN
OUT
10
14
19
15
R5
OUT
R5
IN
EN
SHDN
SHDN
EN
GND
27
SO/SSOP
™ LapLink is a registered trademark of Traveling Software, Inc.
________________________________________________________________ Maxim Integrated Products
1
Ca ll t o ll fre e 1 -8 0 0 -9 9 8 -8 8 0 0 fo r fre e s a m p le s o r lit e ra t u re .
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
ABSOLUTE MAXIMUM RATINGS
VCC ......................................................................... -0.3V to +6V
V+ ................................................................ (VCC - 0.3V) to +6V
V- ............................................................................ +0.3V to -6V
C1A+, C1B+ .................................................. -6V to (V+ + 0.3V)
C1A-, C1B-, C2+ ........................................ -0.3V to (V+ + 0.3V)
C2-.................................................................. (V- - 0.3V) to +6V
Input Voltages
Short-Circuit Duration
TOUT to GND........................................................ Continuous
R
OUT to GND, VCC ................................................ Continuous
Continuous Power Dissipation (TA = +70°C)
SO (derate 12.50mW/°C above +70°C).................. 1000mW
SSOP (derate 9.52mW/°C above +70°C) ................. 762mW
Operating Temperature Ranges:
MAX562
T
R
IN, EN, SHDN ........................................ -0.3V to (VCC + 0.3V)
IN....................................................................................±25V
Output Voltages
OUT ............................................................................... ±15V
OUT ...................................................... -0.3V to (VCC + 0.3V)
MAX562C_ _ ..................................................... 0°C to +70°C
MAX562E_ _ .................................................. -40°C to +85°C
Storage Temperature Range ........................... -65°C to +160°C
Lead Temperature (soldering, 10sec) ........................... +300°C
T
R
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VCC = 2.7V to 5.25V, C1A = C1B = C2 = C4 = 0.33µF, C3 = 0.68µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
EIA/TIA-562 TRANSMITTERS
Output Voltage Swing
CONDITIONS
MIN
TYP
MAX
UNITS
All transmitter outputs loaded with 3kΩ to GND
±3.7
±4.5
±6.0
0.6
V
V
V
CC
= 2.7V to 3.6V
Input Logic Threshold Low
Input Logic Threshold High
T
, EN, SHDN
IN
V
= 5.0V +5%, -10%
= 2.7V to 3.6V
0.8
CC
V
CC
1.8
3.0
T
IN
, EN, SHDN
V
V
CC
= 5.0V +5%, -10%
Output Leakage Current
Output Resistance
±10
±60
±25
2.4
µA
Ω
V
= V+ = V- = 0V, V
= ±2V
300
CC
OUT
Output Short-Circuit Current
EIA/TIA-562 RECEIVERS
Input Voltage Operating Range
Input Threshold Low
Input Threshold High
Input Hysteresis
V
OUT
= 0V
mA
V
V
0.8
3
V
No hysteresis when SHDN = 0V
-15V < V < 15V
0.3
5
V
Input Resistance
7
kΩ
V
IN
Output Voltage Low
I
= 1.6mA
= -1.0mA
0.4
OUT
Output Voltage High
Output Leakage Current
POWER SUPPLY
I
V
-0.5
V
OUT
CC
EN = GND, 0V ≤ R
≤ V
CC
0.05
±10
µA
OUT
Operating Supply Voltage
2.7
5.25
33
V
No load
All outputs loaded 3kΩ
20
24
V
Power-Supply Current
V
CC
= 3.3V
mA
CC
Shutdown Supply Current with
Receivers Active
EN = V
,
SHDN = GND, T = +25°C
45
1
130
50
µA
µA
CC
A
Shutdown Supply Current
SHDN = EN = GND, T = +25°C
A
2
_______________________________________________________________________________________
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
MAX562
AC CHARACTERISTICS
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
1000pF || 3kΩ load each transmitter output,
150pF load each receiver output
Data Rate
230.4
280.0
kbits/sec
C
R
= 50pF to 2500pF,
= 3kΩ to 7kΩ. Measured from +3V to -3V, or
L
L
Transmitter Slew Rate
4
6
30
V/µs
-3V to +3V
R
= 3kΩ measured
L
C
C
= 2500pF
= 1000pF
0.22
0.22
3.1
2.1
L
L
Transmitter Rise/Fall Time
from +3.3V to -3.3V
or -3.3V to +3.3V
µs
ns
t
t
t
t
900
1000
100
1700
1700
PHLT
PLHT
ET
2500pF || 3kΩ load,
Transmitter Propagation Delay
Figure 1
Transmitter-Output Enable Time
Transmitter-Output Disable Time
µs
ns
Figure 3
600
DT
t
100
250
PHLR
C
= 150pF,
Receiver Propagation Delay,
Normal Operation
L
ns
ns
SHDN = V
CC
Figure 2
t
t
t
250
3000
2000
500
4000
3000
PLHR
PHLS
PLHS
C
= 150pF,
L
Receiver Propagation Delay,
Keep-Awake Mode
SHDN = GND
Figure 2
Receiver-Output Enable Time
Receiver-Output Disable Time
Figure 4
Figure 4
t
t
100
250
250
500
ns
ns
ER
DR
_______________________________________________________________________________________
3
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
__________________________________________Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s
(VCC = 3.3V, C1A = C1B = C2 = C4 = 0.33µF, C3 = 0.68µF, T =+25°C, unless otherwise noted.)
A
TRANSMITTER SLEW RATE
vs. LOAD CAPACITANCE
TRANSMITTER OUTPUT VOLTAGE
vs. TEMPERATURE
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE, TO 231kbps
8.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0
6
6
5
5
4
T_
+
OUT
ALL OUTPUTS LOADED
T_
+
OUT
MAX562
4
3kΩ II C
.....
L
+3.7V EIA/TIA-562
ALL TRANSMITTERS LOADED 3kΩ
-3.7V EIA/TIA-562
3
3
ALL TRANSMITTERS
LOADED 3kΩ II C
2
2
L
1
1
SLEW+
SLEW-
0
0
-1
-2
-3
-4
-5
-6
-1
-2
-3
-4
-5
-6
.....
T_
-
OUT
T_
-
OUT
0
1000
2000
3000
4000 5000
0
1000
2000
3000
4000 5000
-40
80
0
40
C (pF)
L
TEMPERATURE (°C)
C (pF)
L
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
SUPPLY CURRENT
vs. TRANSMITTER DATA RATE
SUPPLY CURRENT
vs. TEMPERATURE
38
36
34
32
30
28
26
24
22
20
38
36
34
32
30
28
26
24
22
55
50
45
40
35
30
25
20
ALL TRANSMITTERS LOADED 3kΩ
V
= +2.7V
CC
3 OUTPUTS LOADED
3kΩ II 2500pF
ALL TRANSMITTERS LOADED 3kΩ
2 OUTPUTS LOADED
3kΩ II 2500pF
V
CC
= +3.3V
1 OUTPUT LOADED
3kΩ II 2500pF
100
200
250
4.5
5.0
5.5
50
150
2.5
3.0
3.5
4.0
(V)
0
-40
80
0
40
V
DATA RATE (kbps)
CC
TEMPERATURE (°C)
SUPPLY CURRENT
vs. TEMPERATURE
60
55
50
45
40
35
SHDN = 0, EN = 1
ALL TRANSMITTERS LOADED 3kΩ
V
CC
= +3.3V
V
CC
= +2.7V
40
-40
80
0
TEMPERATURE (°C)
4
_______________________________________________________________________________________
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
MAX562
______________________________________________________________P in De s c rip t io n
PIN
NAME
V+
FUNCTION
Positive charge-pump output, typically 5.8V
28
2, 5
C1A+, C1A-
C1B+, C1B-
Terminals for positive charge-pump capacitor
Terminals for positive charge-pump capacitor
TTL/CMOS Receiver Outputs.
3, 4
6, 7, 8, 9, 10
R_
OUT
11, 12, 13
T_
IN
TTL/CMOS Driver Inputs
14
EN
Receiver Enable, see Shutdown and Enable Control section.
Shutdown Control, see Shutdown and Enable Control section.
EIA/TIA-562 Driver Outputs
15
SHDN
16, 17, 18
T_
OUT
19, 20, 21, 22, 23
R_
IN
EIA/TIA-562 Receiver Inputs
24, 25
26
C2+, C2-
V-
Terminals for negative charge-pump capacitor
Negative charge-pump output, typically -5.2V
Ground
27
GND
1
V
+2.7V to +5.25V Supply Voltage
CC
+3V
+3V
INPUT
50%
50%
0V
INPUT
0V
V
0V
V
OL
OH
V
CC
OUTPUT
50%
50%
GND
OUTPUT
t
t
PHLR
t
t
PLHR
t
t
PLHT
PHLT
PHLS
PLHS
Figure 1. Transmitter Propagation Delay Timing
Figure 2. Receiver Propagation Delay Timing
_______________________________________________________________________________________
5
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
EN
R_
1k
OUT
V
OH
-1V,
+3V
R_
R_
IN
V
OL
+1.6V
SHDN
A. TEST CIRCUIT
0V
150pF
0V
OUTPUT DISABLE TIME (t
)
DT
+3V
EN INPUT
V
OH
EN
OUTPUT ENABLE TIME (t
+3V
MAX562
)
ER
TRANSMITTER
OUTPUTS
0V
V
OH
-3V
RECEIVER
OUTPUTS
V
OL
V
OL
B. ENABLE TIMING
A. TIMING DIAGRAM
1 OR 0
+3V
EN
0V
EN INPUT
T
X
OUTPUT DISABLE TIME (t
)
DR
V
OH
50pF
3k
V
OH
-0.5V
RECEIVER
OUTPUTS
B. TEST CIRCUIT
V
OL
+0.5V
V
OL
C. DISABLE TIMING
Figure 3. Transmitter-Output Disable Timing
Figure 4. Receiver-Output Enable and Disable Timing
EIA/TIA-5 6 2 Drive rs
_______________De t a ile d De s c rip t io n
The driver output voltage is guaranteed to meet the ±3.7V
EIA/TIA-562 specification over the full range of operating
temperatures and voltages, when each transmitter is
loaded with up to 3kΩ and operated up to 230kbps (see
Typical Operating Characteristics). The typical driver out-
put voltage swing exceeds ±4V with a 3kΩ load on all
transmitter outputs. The open-circuit output voltage swing
is typically from (V+ - 0.7V) to (V- + 0.7V). Output swing is
not significantly dependent on VCC since the charge
pumps are regulated.
The MAX562 has three sections: the charge-pump voltage
converter, the drivers (transmitters), and the receivers.
Ch a rg e -P u m p Vo lt a g e Co n ve rt e r
The charge-pump voltage converter is used to produce a
positive and a negative supply to drive the transmitters. The
positive voltage (V+) is generated by a regulated charge
pump working as either a doubler or a tripler (depending on
the V level) and using capacitors C1A, C1B and C3 (see
TypicCaCl Operating Circuit). The negative voltage (V-) derives
from V+ using a simple charge-pump inverter that employs
capacitors C2 and C4.
Input thresholds are CMOS and TTL compatible. Connect
unused inputs to VCC or to GND.
When SHDN is low, the driver outputs are off and their leak-
age currents are less than 10µA, even if the transmitter
outputs are back-driven between -7V and +15V. Taking
SHDN low does not disable the receivers.
These charge-pump converters are regulated to give output
voltages of +5.8V and -5.2V. Having regulated supplies
generated on-chip makes the MAX562's performance insen-
sitive to variations in VCC from 2.7V to 5.25V, transmitter load-
ing changes, and operating temperature changes.
When SHDN and EN are both low, the entire chip is
disabled and all outputs are high impedance. Power
consumption is lowest in this condition. Exiting shutdown
takes about 100µs, but depends on VCC. Figure 5 shows
When SHDN is low, the charge pumps are disabled, V+ is
internally connected to VCC, and V- is internally connected to
GND.
6
_______________________________________________________________________________________
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
MAX562
The guaranteed 0.8V and 2.4V receiver input thresh-
olds are significantly tighter than the ±3.0V thresholds
required by the EIA/TIA-562 specification. This allows
the receiver inputs to respond to TTL/CMOS logic lev-
e ls a s we ll a s EIA/TIA-562/232 le ve ls . Als o, the
MAX562's guaranteed 0.8V lower threshold ensures
that receivers shorted to ground will have a logic 1 out-
put. The 5kΩ input resistance to ground ensures that a
5
0
SHDN
6
4
2
0
V
CC
= +2.2V
V
CC
= +2.7V
V
CC
= +3.3V
V
CC
= +5.0V
receiver with its input left open will also have a logic 1
output.
-2
-4
The receiver inputs have approximately 0.3V hysteresis
when SHDN is high. This provides clean output transi-
tions, even with slowly moving input signals with mod-
erate noise and ringing.
0
100
200
300
TIME (µs)
The receivers are active when EN is high. When EN is
low, the receiver outputs are high impedance. This
allows wire-OR connection of two EIA/TIA-562 ports (or
ports of different types) at the UART.
Figure 5. Time for Transmitters to Exit Shutdown
The receivers are always active,when EN is high, irre-
s p e c tive of SHDN's s ta te . Whe n SHDN is hig h, the
receivers have hysteresis and experience the shortest
propagation delays (typically 100ns falling, 250ns ris-
ing). When SHDN is low, the receivers have longer
propagation delays (typically 3µs falling, 2µs rising)
and have no hysteresis. The receiver outputs are not
valid for 50µs after SHDN goes low.
the MAX562 transmitter outputs when SHDN rises. Two
transmitter outputs are shown going to opposite EIA/TIA-
562 levels (one transmitter input is high, the other is low).
Each transmitter is loaded with 3kΩ in parallel with
2500pF. The transmitter outputs are well behaved, with
no ringing or undesirable transients as they come out of
shutdown.
Driving Multiple Receivers
S h u t d o w n a n d En a b le Co n t ro l
Each transmitter is designed to drive a single receiver.
Tra ns mitte rs c a n b e p a ra lle le d to d rive multip le
receivers.
SHDN and EN determine the operation of the MAX562
as shown in Table 1.
__________Ap p lic a t io n s In fo rm a t io n
EIA/TIA-5 6 2 Re c e ive rs
All 5 receivers are identical and accept EIA/TIA-562 or
EIA/TIA-232 signals. The CMOS receiver outputs swing
between VCC and GND. They are inverting, maintaining
compatibility with the driver outputs.
Ca p a c it o r S e le c t io n
The capacitor type is not critical for proper MAX562
operation. Any low cost ceramic capacitor (e.g., Z5U,
Y5V) is acceptable for operating at room temperature,
Table 1. MAX562 Control Pin Configurations
CHARGE-PUMP
OPERATION
STATUS
SUPPLY
CURRENT
TYP (A)
TRANSMITTERS
T1-T3
RECEIVERS
R1-R5
SHDN
EN
0
0
1
1
0
1
0
1
Shutdown
Shutdown
High-Z
High-Z
Active
Active
High-Z
Active*
High-Z
Active
1µ
45µ
24m
24m
Normal Operation
Normal Operation
* Active, but with reduced performance (see EIA/TIA-562 Receivers section). This is “keep-awake” mode.
_______________________________________________________________________________________
7
Co m p le t e 2 3 0 k b p s , 2 .7 V t o 5 .2 5 V
S e ria l In t e rfa c e fo r No t e b o o k Co m p u t e rs
Table 2. Summary of EIA/TIA-232E/V.28 and EIA/TIA-562 Specifications
EIA/TIA-232E/V.28
SPECIFICATION
EIA/TIA-562
SPECIFICATION
PARAMETER
CONDITION
Driver Output Voltage
0 Level
5.0V to 15.0V
3.7V to 13.2V
3kΩ to 7kΩ load
1 Level
-5.0V to -15.0V
±25V
-3.7V to -13.2V
±13.2V
MAX562
Maximum Output Level
No load
C
C
= 2500pF
= 1000pF
Up to 20kbps
Up to 20kbps
L
L
Signal Rate (3kΩ ≤ RL ≤ 7kΩ)
Not defined
Up to 64kbps
and X7R ceramic capacitors are recommended for
operation over the full temperature range.
___________________Ch ip To p o g ra p h y
Larger capacitors may be used for C2 and C4 (see
Typical Operating Circuit) to reduce ripple on the trans-
mitter output voltages.
C1B+
3
V
CC
GND
V+ V-
C2+
25
C1A+
2
1
28 27 26
P o w e r-S u p p ly De c o u p lin g
In applications that are sensitive to power-supply noise,
decouple VCC to ground with a capacitor similar in
value to that of the C1A and C1B charge-pump capaci-
tors. Connect the bypass capacitor as close as possi-
ble to the VCC and GND pins.
24
23
C2-
4
5
C1B-
C1A-
0. 164"
(4. 166mm)
V+ a n d V- a s P o w e r S u p p lie s
R1
IN
A small amount of power can be drawn from V+ and V-.
Excessive loads will cause V+ and V- to fall out of
regulation. When V+ or V- are loaded, check for good
regulation over the intended operating temperature
range.
6
7
8
R1
OUT
OUT
OUT
22
21
R2
R3
IN
IN
R2
R3
20
19
9
R4
R5
IN
IN
R4
R5
OUT
OUT
10
11 12 13 14 15
16
T3
17
18
T1
T2
IN
EN
IN SHDN
IN
T3
OUT
OUT
T1
T2
OUT
0. 135"
(3. 429mm)
Substrate connected to V+
Transistor count: 1892
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8
___________________Ma x im In t e g ra t e d P ro d u c t s , 1 2 0 S a n Ga b rie l Drive , S u n n yva le , CA 9 4 0 8 6 (4 0 8 ) 7 3 7 -7 6 0 0
© 1993 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
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