SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
D
D
D
D
D
D
D
Meets or Exceeds the Requirements of
ANSI TIA/EIA-644 Standard
Operates With a Single 3.3-V Supply
Designed for Signaling Rate of up to
155 Mbps
Differential Input Thresholds ± 100 mV Max
Low-Voltage TTL (LVTTL) Logic Output
Levels
Open-Circuit Fail Safe
Characterized For Operation From
0°C to 70°C
SN75LVDS32D (Marked as 75LVDS32)
SN75LVDS32PW (Marked as DS32)
(TOP VIEW)
1B
1A
1Y
G
2Y
2A
2B
GND
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
VCC
4B
4A
4Y
G
3Y
3A
3B
SN75LVDS9637D (Marked as DF637 or 7L9637)
SN75LVDS9637DGK (Marked as AXI)
(TOP VIEW)
description
The SN75LVDS32 and SN75LVDS9637 are
differential line receivers that implement the
VCC
1A
1
8
electrical characteristics of low-voltage differential
1Y
7
2
1B
signaling (LVDS). This signaling technique lowers
2Y
3
6
2A
the output voltage levels of 5-V differential
GND
4
5
2B
standard levels (such as EIA/TIA-422B) to reduce
the power, increase the switching speeds, and
allow operation with a 3.3-V supply rail. Any of the four differential receivers provides a valid logical output state
with a ±100 mV allow operation with a differential input voltage within the input common-mode voltage range.
The input common-mode voltage range allows 1 V of ground potential difference between two LVDS nodes.
The intended application of these devices and signaling technique is both point-to-point and multidrop (one
driver and multiple receivers) data transmission over controlled impedance media of approximately 100 Ω. The
transmission media may be printed-circuit board traces, backplanes, or cables. The ultimate rate and distance
of data transfer is dependent upon the attenuation characteristics of the media and the noise coupling to the
environment.
The SN75LVDS32 and SN75LVDS9637 are characterized for operation from 0°C to 70°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright 2001 Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
logic diagram
’LVDS32 logic diagram
(positive logic)
G
G
1A
1B
’LVDS9637D logic diagram
(positive logic)
4
1A
12
2
1B
6
2A
2
1Y
7
6
3
3
2A
1Y
1
8
2Y
5
2B
5
2Y
7
2B
3A
3B
4A
4B
10
11
9
14
15
13
3Y
4Y
Function Tables
SN75LVDS32
DIFFERENTIAL INPUT
ENABLES
G
G
Y
VID ≥ 100 mV
H
X
X
L
H
H
–100 mV < VID < 100 mV
H
X
X
L
?
?
VID ≤ –100 mV
H
X
X
L
L
L
X
L
H
Z
Open
H
X
X
L
H
H
H = high level, L = low level, X = irrelevant,
Z = high impedance (off), ? = indeterminate
2
OUTPUT
A, B
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
logic symbol†
SN75LVDS32
G
G
1A
1B
2A
2B
3A
3B
4A
4B
4
≥1
EN
12
2
3
1Y
1
5
6
2Y
7
10
11
3Y
9
14
13
15
4Y
† This symbol is in accordance with ANSI/IEEE Std
91-1984 and IEC Publication 617-12.
Function Table
logic symbol†
SN75LVDS9637
SN75LVDS9637
DIFFERENTIAL INPUT
OUTPUT
A, B
Y
VID ≥ 100 mV
–100 mV < VID < 100 mV
H
1A
1B
2A
?
VID ≤ –100 mV
L
Open
H
H = high level, L = low level, ? = indeterminate
POST OFFICE BOX 655303
2B
8
7
6
5
2
3
1Y
2Y
† This symbol is in accordance with ANSI/IEEE Std
91-1984 and IEC Publication 617-12.
• DALLAS, TEXAS 75265
3
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
equivalent input and output schematic diagrams
EQUIVALENT OF EACH A OR B INPUT
EQUIVALENT OF G, G, 1,2EN OR
3,4EN INPUTS
VCC
VCC
300 kΩ
TYPICAL OF ALL OUTPUTS
VCC
300 kΩ
50 Ω
5Ω
Input
Y Output
A Input
7V
B Input
7V
7V
7V
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 4 V
Input voltage range, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to VCC + 0.5 V
Input voltage range, VI (A or B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 4 V
Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Dissipation Rating Table
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 65_C to 150_C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260_C
† 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 under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: All voltages, except differential I/O bus voltages, are with respect to the network ground terminal.
DISSIPATION RATING TABLE
PACKAGE
TA ≤ 25°C
POWER RATING
DERATING FACTOR‡
ABOVE TA = 25°C
TA = 70°C
POWER RATING
D (8)
725 mW
5.8 mW/°C
464 mW
D (16)
950 mW
7.6 mW/°C
608 mW
PW
774 mW
6.2 mW/°C
496 mW
DGK
425 mW
3.4 mW/°C
272 mW
‡ This is the inverse of the junction-to-ambient thermal resistance when board mounted and with
no air flow.
4
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
recommended operating conditions
MIN
Supply voltage, VCC
3
High-level input voltage, VIH
G, G
Low-level input voltage, VIL
G, G
NOM
MAX
3.3
3.6
2
Magnitude of differential input voltage, |VID|
|V
ID
2
Operating free-air temperature, TA
|
2.4
0
V
V
0.1
Common-mode input voltage, VIC (see Figure 1)
UNIT
0.8
V
0.6
V
* | V2ID|
V
VCC – 0.8
70
V
°C
VIC – Common Mode Input Voltage Range – V
COMMON-MODE INPUT VOLTAGE RANGE
vs
DIFFERENTIAL INPUT VOLTAGE
2.5
2
Max at VCC >3.15 V
Max at VCC = 3 V
1.5
1
ÁÁ
ÁÁ
0.5
Min
0
0
0.1
0.2
0.3
0.4
0.5
VID – Differential Input Voltage – V
0.6
Figure 1. VIC Versus VID and VCC
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
5
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
SN75LVDSxxxx electrical characteristics over recommended operating conditions (unless
otherwise noted)
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁ
ÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
PARAMETER
TEST CONDITIONS
VITH+
VITH–
Positive-going differential input voltage threshold
VOH
VOL
High-level output voltage
ICC
See Figure 2 and Table 1
Negative-going differential input voltage threshold‡
IOH = –8 mA
IOL = 8 mA
Low-level output voltage
SN75LVDS32
Supply current
SN75LVDS9637
II
Input current (A or B inputs)
II(OFF)
IIH
Power-off input current (A or B inputs)
Enabled,
100
–100
10
18
Disabled
0.25
0.5
No load
5.5
10
–2
–10
– 20
– 1.2
–3
VCC = 0,
VIH = 2 V
VI = 3.6 V
mV
V
0.4
No load
UNIT
mV
2.4
VI = 0
VI = 2.4 V
High-level input current (G, or G inputs)
SN75LVDS32,
SN75LVDS9637
MIN TYP†
MAX
6
V
mA
µA
20
µA
10
µA
IIL
Low-level input current (G, or G inputs)
VIL = 0.8 V
10
µA
IOZ
High-impedance output current
VO = 0 or VCC
± 10
µA
† All typical values are at TA = 25°C and with VCC = 3.3 V.
‡ The algebraic convention, in which the less positive (more negative) limit is designated minimum, is used in this data sheet for the negative-going
differential input voltage threshold only.
SN75LVDSxxxx switching characteristics over recommended operating conditions (unless
otherwise noted)
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
Á
ÁÁÁ
ÁÁ
Á
ÁÁÁ
ÁÁ
Á
ÁÁÁ
ÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
ÁÁÁ
PARAMETER
TEST CONDITIONS
SN75LVDS32,
SN75LVDS9637
MIN TYP†
MAX
UNIT
tpLH
tpHL
Propagation delay time, low-to-high-level output
2.1
6
ns
Propagation delay time, high-to-low-level output
2.1
6
ns
tsk(p)
tsk(o)
Pulse skew (|tPHL – tPLH|)
0.6
1.5
ns
0.7
1.5
ns
0.6
ns
0.6
ns
1
ns
25
ns
25
ns
25
ns
tsk(pp)
tr
Channel-to-channel output skew†
Part-to-part skew‡
CL = 100 pF, See Figure 3
Output signal rise time, 20% to 80%
tf
tpHZ
Output signal fall time, 80% to 20%
tpLZ
tpZH
Propagation delay time, low-level-to-high-impedance output
Propagation delay time, high-level-to-high-impedance output
Propagation delay time, high-impedance-to-high-level output
See Figure 4
tpZL
Propagation delay time, high-impedance-to-low-level output
25
ns
† All typical values are at 25°C and with a 3.3-V supply.
‡ tsk(p) is the magnitude of the time difference between the high-to-low and low-to-high propagation delay times at an output
§ tsk(o) is the magnitude of the time difference between the outputs of a single device with all of their inputs connected together.
¶ tsk(pp) is the magnitude of the difference in propagation delay times between any specified terminals of two devices when both devices operate
with the same supply voltages, same temperature, and have identical packages and test circuits.
6
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
PARAMETER MEASUREMENT INFORMATION
A
Y
VID
B
(VIA + VIB)/2
VIA
VIC
VO
VIB
Figure 2. Voltage Definitions
ÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁ
Table 1. Receiver Minimum and Maximum Input Threshold Test Voltages
APPLIED
VOLTAGES
RESULTING DIFFERENTIAL
INPUT VOLTAGE
RESULTING COMMONMODE INPUT VOLTAGE
VIA
1.25 V
VIB
1.15 V
VID
100 mV
VIC
1.2 V
1.15 V
1.25 V
–100 mV
1.2 V
2.4 V
2.3 V
100 mV
2.35 V
2.3 V
2.4 V
–100 mV
2.35 V
0.1 V
0V
100 mV
0.05 V
0V
0.1 V
–100 mV
0.05 V
1.5 V
0.9 V
600 mV
1.2 V
0.9 V
1.5 V
–600 mV
1.2 V
2.4 V
1.8 V
600 mV
2.1 V
1.8 V
2.4 V
–600 mV
2.1 V
0.6 V
0V
600 mV
0.3 V
0V
0.6 V
–600 mV
0.3 V
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
7
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
PARAMETER MEASUREMENT INFORMATION
VID
VIA
CL 10 pF
VIB
VO
VIA
1.4 V
VIB
1V
0.4 V
0
–0.4 V
VID
tPHL
tPLH
80%
VO
20%
80%
20%
VOH
1.4 V
VOL
tf
tr
NOTES: A. All input pulses are supplied by a generator having the following characteristics: tr or tf ≤ 1 ns, pulse repetition rate
(PRR) = 50 Mpps, pulse width = 10 ± 0.2 ns.
B. CL includes instrumentation and fixture capacitance within 6 mm of the D.U.T.
Figure 3. Timing Test Circuit and Wave Forms
8
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
PARAMETER MEASUREMENT INFORMATION
B
1.2 V
500 Ω
A
G
Inputs
(see Note A)
10 pF
(see Note B)
±
VO
VTEST
G
2.5 V
VTEST
A
G
1V
2V
1.4 V
0.8 V
G
2V
1.4 V
0.8 V
tPLZ
tPLZ
tPZL
tPZL
Y
VTEST
2.5 V
1.4 V
VOL +0.5 V
VOL
0
1.4 V
A
2V
1.4 V
0.8 V
G
2V
1.4 V
0.8 V
tPHZ
G
tPHZ
tPZH
tPZH
VOH
VOH –0.5 V
Y
1.4 V
0
NOTES: A. All input pulses are supplied by a generator having the following characteristics: tr or tf ≤ 1 ns, pulse repetition rate
(PRR) = 0.5 Mpps, pulse width = 500 ± 10 ns.
B. CL includes instrumentation and fixture capacitance within 6 mm of the D.U.T.
Figure 4. Enable/Disable Time Test Circuit and Wave Forms
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
9
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
APPLICATION INFORMATION
using an LVDS receiver with RS-422 data
Receipt of data from a TIA/EIA-422 line driver may be accomplished using a TIA/EIA-644 line receiver with the
addition of an attenuator circuit. This technique gives the user a very high-speed and low-power 422 receiver.
If the ground noise between the transmitter and receiver is not a concern (less than ±1 V), the answer can be
as simple as shown below in Figure 5. The use of a resistor divider circuit in front of the LVDS receiver attenuates
the 422 differential signal to LVDS levels.
The resistors present a total differential load of 100 Ω to match the characteristic impedance of the transmission
line and to reduce the signal 10:1. The maximum 422 differential output signal or 6 V is reduced to 600 mV. The
high input impedance of the LVDS receiver prevents input bias offsets and maintains a better than 200-mV
differential input voltage threshold at the inputs to the divider. This circuit is used in front of each LVDS channel
that also receives 422 signals.
R1
45.3 Ω
’LVDS32
R3
5.11 Ω
A
R4
5.11 Ω
B
Y
R2
45.3 Ω
NOTE A: The components used were standard values.
R1, R2 = NRC12F45R3TR, NIC Components, 45.3 Ohm, 1/8W, 1%, 1206 Package
R3, R4 = NRC12F5R11TR, NIC Components, 5.11 Ohm, 1/8W, 1%, 1206 Package
The resistor values do not need to be 1% tolerance. However, it can be difficult locating a supplier of resistors having values less than
100 Ω in stock and readily available. The user may find other suppliers with comparable parts having tolerances of 5% or even 10%.
These parts are adequate for use in this circuit.
Figure 5. RS-422 Data Input to an LVDS Receiver Under Low Ground Noise Conditions
If ground noise between the RS-422 driver and LVDS receiver is a concern, then the common-mode voltage
must be attenuated. The circuit must then be modified to connect the node between R3 and R4 to the LVDS
receiver ground. This modification to the circuit increases the common-mode voltage from ±1 V to greater than
±4.5 V.
10
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
APPLICATIONS INFORMATION
The devices are generally used as building blocks for high-speed point-to-point data transmission where ground
differences are less than 1 V. Devices can interoperate with RS-422, PECL, and IEEE-P1596. Drivers/receivers
approach ECL speeds without the power and dual supply requirements.
TRANSMISSION DISTANCE
vs
SIGNALING RATE
Transmission Distance – m
100
30% Jitter
(see Note A)
10
5% Jitter
(see Note A)
1
24 AWG UTP 96 Ω
(PVC Dielectric)
0.1
10
100
1000
Signaling Rate – Mbps
NOTE A: This parameter is the percentage of distortion of the unit interval (UI) with a pseudorandom data pattern.
Figure 6. Typical Transmission Distance vs Signaling Rate
1
1B
VCC
16
0.1 µF
(see Note A)
100 Ω
2
3
VCC 4
5
6
1A
4B
2Y
4Y
G
2A
100 Ω
7
4A
2B
3Y
3A
0.001 µF
(see Note A)
15
1Y
G
3.3 V
14
100 Ω
(see Note B)
13
12
11
See Note C
10
100 Ω
8
GND
3B
9
NOTES: A. Place a 0.1 µF and a 0.001 µF Z5U ceramic, mica or polystyrene dielectric, 0805 size, chip capacitor between VCC and the ground
plane. The capacitors should be located as close as possible to the device terminals.
B. The termination resistance value should match the nominal characteristic impedance of the transmission media with ±10%.
C. Unused enable inputs should be tied to VCC or GND as appropriate.
Figure 7. Typical Application Circuit Schematic
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
11
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
APPLICATION INFORMATION
1/4 ’LVDS31
Strb/Data_TX
TpBias on
Twisted-Pair A
Strb/Data_Enable
TP
55 Ω
’LVDS32
5 kΩ
Data/Strobe
55 Ω
3.3 V
TP
20 kΩ
500 Ω
VG on
Twisted-Pair B
1 Arb_RX
500 Ω
20 kΩ
3.3 V
20 kΩ
500 Ω
2 Arb_RX
500 Ω
20 kΩ
3.3 V
7 kΩ
Twisted-Pair B Only
7 kΩ
10 kΩ
Port_Status
3.3 kΩ
NOTES: A.
B.
C.
D.
Resistors are leadless thick-film (0603) 5% tolerance.
Decoupling capacitance is not shown but recommended.
VCC is 3 V to 3.6 V.
The differential output voltage of the ’LVDS31 can exceed that allowed by IEEE1394.
Figure 8. 100-Mbps IEEE 1394 Transceiver
12
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
APPLICATION INFORMATION
fail safe
One of the most common problems with differential signaling applications is how the system responds when
no differential voltage is present on the signal pair. The LVDS receiver is like most differential line receivers, in
that its output logic state can be indeterminate when the differential input voltage is between –100 mV and
100 mV if it is within its recommended input common-mode voltage range. TI’s LVDS receiver is different in how
it handles the open-input circuit situation, however.
Open-circuit means that there is little or no input current to the receiver from the data line itself. This could be
when the driver is in a high-impedance state or the cable is disconnected. When this occurs, the LVDS receiver
will pull each line of the signal pair to near VCC through 300-kΩ resistors as shown in Figure 9. The fail-safe
feature uses an AND gate with input voltage thresholds at about 2.3 V to detect this condition and force the
output to a high level, regardless of the differential input voltage.
VCC
300 kΩ
300 kΩ
A
Rt
Y
B
VIT ≈ 2.3 V
Figure 9. Open-Circuit Fail Safe of the LVDS Receiver
It is only under these conditions that the output of the receiver will be valid with less than a 100-mV differential
input voltage magnitude. The presence of the termination resistor, Rt, does not affect the fail-safe function as
long as it is connected as shown in the figure. Other termination circuits may allow a dc current to ground that
could defeat the pullup currents from the receiver and the fail-safe feature.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
13
SN75LVDS32, SN75LVDS9637
HIGH-SPEED DIFFERENTIAL LINE RECEIVERS
SLLS360B – JUNE 1999 – REVISED JUNE 2001
APPLICATION INFORMATION
0.01 µF
1
VCC
16
0.1 µF
(see Note A)
1B
100 Ω
2
3
VCC 4
5
6
1A
4B
2Y
4Y
G
2A
100 Ω
7
4A
2B
3Y
3A
5V
1N645
(2 places)
15
1Y
G
≈3.6 V
14
100 Ω
(see Note B)
13
12
11
See Note C
10
100 Ω
8
GND
3B
9
NOTES: A. Place a 0.1 µF Z5U ceramic, mica or polystyrene dielectric, 0805 size, chip capacitor between VCC and the ground plane. The
capacitor should be located as close as possible to the device terminals.
B. The termination resistance value should match the nominal characteristic impedance of the transmission media with ±10%.
C. Unused enable inputs should be tied to VCC or GND as appropriate.
Figure 10. Operation With 5-V Supply
related information
IBIS modeling is available for this device. Please contact the local TI sales office or the TI Web site at www.ti.com
for more information.
For more application guidelines, please see the following documents:
D
D
D
D
D
D
14
Low-Voltage Differential Signalling Design Notes (TI literature SLLA014)
Interface Circuits for TIA/EIA-644 (LVDS) (TI literature SLLA038)
Reducing EMI with LVDS (TI literature SLLA030)
Slew Rate Control of LVDS Circuits (TI literature SLLA034)
Using an LVDS Receiver with RS-422 Data (TI literature SLLA031)
Evaluating the LVDS EVM (TI literature SLLA033)
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
SN75LVDS32D
ACTIVE
SOIC
D
16
40
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
75LVDS32
SN75LVDS32DR
ACTIVE
SOIC
D
16
2500
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
75LVDS32
SN75LVDS9637D
ACTIVE
SOIC
D
8
75
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
DF637
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of