SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
D
D
D
D
D
D
D
D
D
D
D
Improved Speed and Package Replacement
for the SN75LBC976
Designed to Operate at up to 20 Million
Data Transfers per Second (Fast-20 SCSI)
Nine Differential Channels for the Data and
Control Paths of the Small Computer
Systems Interface (SCSI) and Intelligent
Peripheral Interface (IPI)
SN75976A Packaged in Shrink
Small-Outline Package with 25-Mil Terminal
Pitch (DL) and Thin Shrink Small-Outline
Package with 20-Mil Terminal Pitch (DGG)
SN55976A Packaged in a 56-Pin Ceramic
Flat Pack (WD)
Two Skew Limits Available
ESD Protection on Bus Terminals
Exceeds 12 kV
Low Disabled Supply Current 8 mA Typ
Thermal Shutdown Protection
Positive- and Negative-Current Limiting
Power-Up/Down Glitch Protection
description
SN75976A DGG or DL
SN55976A WD
(TOP VIEW)
GND
BSR
CRE
1A
1DE/RE
2A
2DE/RE
3A
3DE/RE
4A
4DE/RE
VCC
GND
GND
GND
GND
GND
VCC
5A
5DE/RE
6A
6DE/RE
7A
7DE/RE
8A
8DE/RE
9A
9DE/RE
1
56
2
55
3
54
4
53
5
52
6
51
7
50
8
49
9
48
10
47
11
46
12
45
13
44
14
43
15
42
16
41
17
40
18
39
19
38
20
37
21
36
22
35
CDE2
CDE1
CDE0
9B+
9B–
8B+
8B –
7B+
7B –
6B+
6B –
VCC
GND
GND
GND
GND
GND
VCC
5B+
5B –
4B+
4B –
3B+
3B –
2B+
2B –
1B+
1B –
The SN75976A is an improved replacement for
23
34
the
industry’s
first
9-channel
RS-485
24
33
transceiver — the SN75LBC976. The A version
25
32
offers improved switching performance, a smaller
26
31
package, and higher ESD protection. The
27
30
SN75976A is offered in two versions. The ’976A2
28
29
skew limits of 4 ns for the differential drivers and
5 ns for the differential receivers complies with the
Terminals 13 through 17 and 40 through 44 are
recommended skew budget of the Fast-20 SCSI
connected together to the package lead frame
standard for data transfer rates up to 20 million
and signal ground.
transfers per second. The ’976A1 supports the
Fast SCSI skew budget for 10 million
transfers per second. The skew limit ensures that the propagation delay times, not only from channel-to-channel
but from device-to-device, are closely matched for the tight skew budgets associated with high-speed parallel
data buses.
The patented thermal enhancements made to the 56-pin shrink small-outline package (SSOP) of the SN75976
have been applied to the new, thin shrink, small-outline package (TSSOP). The TSSOP package offers even
less board area requirements than the SSOP while reducing the package height to 1 mm. This provides more
board area and allows component mounting to both sides of the printed circuit boards for low-profile,
space-restricted applications such as small form-factor hard disk drives.
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 1997, 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
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
description (continued)
In addition to speed improvements, the ’976A can withstand electrostatic discharges exceeding 12 kV using
the human-body model, and 600 V using the machine model of MIL-PRF-38535, Method 3015.7 on the RS-485
I/O terminals. This is six times the industry standard and provides protection from the noise that can be coupled
into external cables. The other terminals of the device can withstand discharges exceeding 4 kV and 400 V
respectively.
Each of the nine channels of the ’976A typically meet or exceed the requirements of EIA RS-485 (1983) and
ISO 8482-1987/TIA TR30.2 referenced by American National Standard of Information (ANSI) Systems,
X3.131-1994 (SCSI-2) standard, X2.277-1996 (Fast-20 Parallel Interface), and the Intelligent Peripheral
Interface Physical Layer-ANSI X3.129-1986 standard.
The SN75976A is characterized for operation over an ambient air temperature range of 0°C to 70°C. The
SN55976A is characterized for operation over an ambient air temperature range of – 55°C to 125°C.
AVAILABLE OPTIONS
TA
Skew Limit
(ns)
PACKAGE†
Driver
Receiver
TSSOP
(DGG)
8
9
SN75976A1DGG
SN75976A1DGGR
SN75976A1DL
SN75976A1DLR
—
4
5
SN75976A2DGG
SN75976A2DGGR
SN75976A2DL
SN75976A2DLR
—
8
9
—
—
SN55976A1WD
—
—
SN55976A2WD
0°C to 70°C
55°C to 125°C
–55°C
4
5
† The R suffix indicates taped and reeled packages.
2
POST OFFICE BOX 655303
SSOP
(DL)
• DALLAS, TEXAS 75265
CERAMIC FLAT PACK
(WD)
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
Terminal Functions
TERMINAL
NAME
NO.
Logic
g
Level
I/O
Termination
DESCRIPTION
1A to 9A
4,6,8,10,
19,21,23,
25,27
TTL
I/O
Pullup
1A to 9A carry data to and from the communication controller.
1B – to 9B –
29,31,33,
35,37,.46,
48,50,52
RS-485
I/O
Pulldown
1B – to 9B – are the inverted data signals of the balanced pair to/from
the bus.
1B+ to 9B+
30,32,34,
36,38,47,
49,51,53
RS-485
I/O
Pullup
1B+ to 9B+ are the noninverted data signals of the balanced pair to/from
the bus.
BSR
2
TTL
Input
Pullup
BSR is the bit significant response. BSR disables receivers 1 through 8 and
enables wired-OR drivers when BSR and DE/RE and CDE1 or CDE2 are
high. Channel 9 is placed in a high-impedance state with BSR high.
CDE0
54
TTL
Input
Pulldown
CDE0 is the common driver enable 0. Its input signal enables all drivers
when CDE0 and 1DE/RE – 9DE/RE are high.
CDE1
55
TTL
Input
Pulldown
CDE1 is the common driver enable 1. Its input signal enables drivers
1 to 4 when CDE1 is high and BSR is low.
CDE2
56
TTL
Input
Pulldown
CDE2 is the common driver enable 2. When CDE2 is high and BSR is low,
drivers 5 to 8 are enabled.
CRE
3
TTL
Input
Pullup
CRE is the common receiver enable. When high, CRE disables receiver
channels 5 to 9.
1DE/RE to
9DE/RE
5,7,9,11,
20,22,24,
26,28
TTL
Input
Pullup
1DE/RE–9DE/RE are direction controls that transmit data to the bus when
it and CDE0 are high. Data is received from the bus when
1DE/RE–9DE/RE and CRE and BSR are low and CDE1 and CDE2 are
low.
GND
1,13,14,
15,16,17,
40,41,42,
43,44
NA
Power
NA
GND is the circuit ground. All GND terminals except terminal 1 are
physically tied to the die pad for improved thermal conductivity.†
VCC
12,18,39,
45
NA
Power
NA
Supply voltage
† Terminal 1 must be connected to signal ground for proper operation.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
3
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
logic diagram (positive logic)
CDE0
CDE1
BSR
1A
1DE/RE
2A
2DE/RE
3A
3DE/RE
4A
4DE/RE
CDE2
CRE
5A
5DE/RE
6A
6DE/RE
7A
7DE/RE
8A
8DE/RE
54
55
2
30
4
29
5
6
7
8
9
10
11
Channel 2
Channel 3
Channel 4
9DE/RE
4
32
31
34
33
36
35
2B+
2B–
3B+
3B–
4B+
4B–
56
3
38
19
37
5B+
5B–
20
21
22
23
24
25
26
Channel 6
Channel 7
Channel 8
2
9A
1B+
1B–
27
BSR
3
BSR
47
46
49
48
51
50
6B+
6B–
7B+
7B–
8B+
8B–
54
CRE
CDE0
28
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• DALLAS, TEXAS 75265
53
9B+
52
9B–
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
schematics of inputs and outputs
DE/RE, CRE, BSR, AND
A Inputs
CDE0, CDE1, AND CDE2 Inputs
VCC
VCC
100 kΩ
1 kΩ
1 kΩ
Input
Input
100 kΩ
8V
8V
B + Input
B – Input
VCC
100 kΩ
16 V
VCC
2 kΩ
2 kΩ
16 V
18 kΩ
Input
18 kΩ
Input
100 kΩ
4 kΩ
4 kΩ
16 V
16 V
B + AND B – Outputs
VCC
A Output
VCC
2 kΩ
40 Ω
16 V
18 kΩ
Output
Output
8V
4 kΩ
16 V
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• DALLAS, TEXAS 75265
5
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.3 V to 6 V
Bus voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 10 V to 15 V
Data I/O and control (A side) voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.3 V to VCC +0.5 V
Electrostatic discharge: B side and GND, Class 3, A: (see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 kV
B side and GND, Class 3, B: (see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 V
All terminals, Class 3, A: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 kV
All terminals, Class 3, B: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 V
Continuous total power dissipation (see Note 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . internally limited
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.
NOTES: 1. All voltage values are with respect to the GND terminals.
2. This absolute maximum rating is tested in accordance with MIL-PRF-38535, Method 3015.7.
3. The maximum operating junction temperature is internally limited. Use the Dissipation Rating Table to operate below this
temperature.
DISSIPATION RATING TABLE
PACKAGE
TA ≤ 25°C
OPERATING FACTOR‡
ABOVE TA = 25°C
DGG
2500 mW
20 mW/°C
1600 mW
—
DL
2500 mW
20 mW/°C
1600 mW
—
TA = 70°C
POWER RATING
TA = 125°C
POWER RATING
WD
1300 mW
10.5 mW/°C
827 mW
250 mW
‡ This is the inverse of the junction-to-ambient thermal resistance when board-mounted and with no air flow.
package thermal characteristics
MIN
Junction to ambient thermal resistance
Junction-to-ambient
resistance, RθJA
Junction-to-ambient thermal resistance, RθJA
Junction to case thermal resistance,
Junction-to-case
resistance RθJC
Junction-to-case thermal resistance, RθJC
MAX
UNIT
DGG, board-mounted, no air flow
50
°C/W
DL, board-mounted, no air flow
50
°C/W
95.4
°C/W
DGG
27
°C/W
DL
12
°C/W
5.67
°C/W
165
°C
WD
WD
Thermal-shutdown junction temperature, TJS
6
NOM
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
recommended operating conditions
Supply voltage, VCC
High-level input voltage, VIH
Except nB+, nB–†
Low-level input voltage, VIL
Except nB+, nB–†
Voltage at any bus terminal (separately or common
common-mode),
mode) VO, VI, or VIC
nB+ or nB –
MIN
NOM
MAX
UNIT
4.75
5
5.25
V
2
Low level output current,
Low-level
current IOL
Operating free-air
free air temperature,
temperature TA
12
V
V
– 60
mA
Receiver
–8
mA
Driver
60
mA
8
mA
Receiver
Operating case temperature, TC
V
–7
Driver
High level output current,
High-level
current IOH
V
0.8
SN75976A
0
125
°C
SN75976A
0
70
°C
SN55976A
– 55
125
°C
†n = 1 – 9
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• DALLAS, TEXAS 75265
7
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
S1 to A,
VODH
VODL
VOH
VOL
Driver differential highlevel output
out ut voltage
Driver
D
i
diff
differential
ti l lowl
level output
out ut voltage
High-level output voltage
Low-level output voltage
SN55976A
TYP† MAX
TEST CONDITIONS
VT = 5 V,
See Figure 1
SN75976A
TYP† MAX
UNIT
MIN
MIN
0.7
1
1.8
V
1
1.4
V
S1 to B,
TC ≥ 25°C
S1 to B,
See Figure 1
VT = 5 V,
See Figure 1
VT = 5 V,
0.7
S1 to A,
TC ≥ 25°C
S1 to B,
VT = 5 V,
See Figure 1
0.7
– 1.4
–1
– 1.4
V
See Figure 1
0.7
– 1.8
–1
– 1.8
V
– 0.8
– 1.4
– 0.8
– 1.4
V
4
4.5
4
4.5
V
3
V
VT = 5 V,
S1 to A,
See Figure 1
VT = 5 V,
A side,
IOH = – 8 mA
B side,
VT = 5 V,
A side,
IOH = 8 mA
VID = 200 mV,
See Figure 3
A side,
See Figure 1
VT = 5 V,
See Figure 1
0.8
3
VID = –200 mV,
See Figure 3
0.6
0.8
V
0.6
1
0.8
1
V
V
VIT+
Receiver positive-going differential input
threshold voltage
IOH = – 8 mA,
See Figure 3
0.2
0.2
V
VIT–
Receiver negativegoing differential input
threshold voltage
IOL = 8 mA,
See Figure 3
– 0.2
– 0.2
V
Vhys
Receiver input
hysteresis
(VIT+– VIT–)
VCC = 5 V,
TA = 25°C
II
IIH
Bus input current
High-level
input curg
rent
IIL
Low level input current
Low-level
IOS
Short circuit output
current
IOZ
High-impedance-state
g
output current
ICC
Supply current
24
45
24
45
mV
VIH = 12 V,
VIH = 12 V,
VCC = 5 V,
Other input at 0 V
0.4
1
0.4
1
mA
VCC = 0,
Other input at 0 V
0.5
1
0.5
1
mA
VIH = – 7 V,
VIH = – 7 V,
VCC = 5 V,
Other input at 0 V
– 0.4
– 0.8
– 0.4
– 0.8
mA
VCC = 0,
Other input at 0 V
– 0.3
– 0.8
– 0.3
– 0.8
mA
A, BSR, DE/RE, and CRE,
CDE0, CDE1, and CDE2,
A, BSR, DE/RE, and CRE,
CDE1, CDE1, and CDE2,
VIH = 2 V
VIH = 2V
– 100
– 100
µA
100
100
µA
VIL = 0.8 V
VIL = 0.8 V
– 100
– 100
µA
100
100
µA
±260
±260
mA
nB+ or nB–
A
See IIH and IIL
See IIH and IIL
See II
See II
nB+ or nB–
Disabled
10
10
mA
All drivers enabled, no load
60
60
mA
All receivers enabled, no load
45
45
mA
25
pF
CO
Output capacitance
nB+ or nB– to GND
18
18
Receiver
40
40
pF
Cpd
d
Power dissipation
capacitance
(see Note 4)
100
100
pF
Driver
† All typical values are at VCC = 5 V, TA = 25°C.
NOTE 4: Cpd determines the no-load dynamic supply current consumption, IS = CPD × VCC × f + ICC
8
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
driver switching characteristics over recommended operating conditions (unless otherwise
noted)
PARAMETER
TEST CONDITIONS
SN75976A
TYP†
MAX
MIN
2.5
13.5
ns
3
11
ns
5
13
ns
4.5
11.5
ns
5
9
ns
7
11
ns
’976A1
8
ns
’976A2
4
ns
4
ns
’976A1
tpd
d
Propagation
delay
g
y time,, tPHL or tPLH
(see Figures 1 and 2)
’976A2
tsk(lim)
k(li )
Skew limit,, maximum tpd
d – minimum tpd
d
(see Note 5)
UNIT
VCC = 5 V,
VCC = 5 V,
TC = 25°C
TC = 100°C
VCC = 5 V,
VCC = 5 V,
TC = 25°C
TC = 100°C
tsk(p)
tf
Pulse skew, |tPHL – tPLH|
Fall time
S1 to B,
tr
ten
Rise time
See Figure 2
tdis
tPHZ
Disable time, control inputs to high-impedance output
tPLZ
tPZH
Propagation delay time, low-level to high-impedance output
See Figure 2
4
ns
8
ns
Enable time, control inputs to active output
Propagation delay time, high-level to high-impedance output
See Figures 5 and 6
Propagation delay time, high-impedance to high-level output
50
ns
100
ns
17
100
ns
25
100
ns
17
50
ns
tPZL
Propagation delay time, high-impedance to low-level output
17
50
ns
† All typical values are at VCC = 5 V, TA = 25°C.
NOTE 5: This parameter is applicable at one VCC and operating temperature within the recommended operating conditions and to any two
devices.
driver switching characteristics over recommended operating conditions (unless otherwise
noted)
PARAMETER
tpd
d
tsk(lim)
k(li )
TEST CONDITIONS
Propagation
g
delay
y time,, tPHL or tPLH
(see Figures 1 and 2)
’976A1
Skew limit,, maximum tpd
d – minimum tpd
d
(see Note 5)
15
ns
ns
’976A1
8
ns
’976A2
4
ns
4
ns
tsk(p)
tf
Pulse skew, |tPHL – tPLH|
Fall time
S1 to B,
tr
ten
Rise time
See Figure 2
tdis
tPHZ
tPLZ
tPZH
TA = 25°C
TA = 25°C
UNIT
13.5
’976A2
VCC = 5 V,
VCC = 5 V,
SN55976A
TYP†
MAX
MIN
See Figure 2
Enable time, control inputs to active output
4
ns
8
ns
60
ns
Disable time, control inputs to high-impedance output
140
ns
Propagation delay time, high-level to high-impedance output
120
ns
Propagation delay time, low-level to high-impedance output
120
ns
60
ns
Propagation delay time, high-impedance to high-level output
See Figures 5 and 6
tPZL
Propagation delay time, high-impedance to low-level output
60
ns
† All typical values are at VCC = 5 V, TA = 25°C.
NOTE 5. This parameter is applicable at one VCC and operating temperature within the recommended operating conditions and to any two
devices.
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9
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
receiver switching characteristics over recommended operating conditions (unless otherwise
noted)
PARAMETER
TEST CONDITIONS
’976A1
tpd
d
Propagation
g
delay
y time,, tPHL or tPLH
(see Figures 3 and 4)
tsk(lim)
k(li )
Skew limit,, maximum tpd
d – minimum tpd
d
(see Note 5)
’976A2
VCC = 5 V,
VCC = 5 V,
TC = 25°C
TC = 100°C
SN75976A
TYP†
MAX
MIN
UNIT
7.5
16.5
ns
8.5
14.5
ns
8.6
13.6
ns
9
14
ns
’976A1
9
ns
’976A2
5
ns
4
ns
tsk(p)
tt
Pulse skew, |tPHL – tPLH|
0.6
ten
tdis
Enable time, control inputs to active output
50
ns
Disable time, control inputs to high-impedance output
60
ns
tPHZ
tPLZ
Propagation delay time, high-level to high-impedance output
60
ns
50
ns
tPZH
tPZL
Propagation delay time, high-impedance to high-level output
50
ns
50
ns
Transition time (tr or tf)
See Figure 4
Propagation delay time, low-level to high-impedance output
2
See Figures 7 and 8
Propagation delay time, high-impedance to low-level output
ns
† All typical values are at VCC = 5 V, TA = 25°C.
NOTE 5. This parameter is applicable at one VCC and operating temperature within the recommended operating conditions and to any two
devices.
receiver switching characteristics over recommended operating conditions (unless otherwise
noted)
PARAMETER
tpd
d
tsk(lim)
k(li )
TEST CONDITIONS
Propagation
g
delay
y time,, tPHL or tPLH
(see Figures 3 and 4)
Skew limit,, maximum tpd
d – minimum tpd
d
(see Note 5)
’976A1
’976A2
VCC = 5 V,
VCC = 5 V,
SN55976A
TYP†
MAX
MIN
TA = 25°C
TA = 25°C
’976A1
’976A2
0.6
UNIT
19
ns
16
ns
9
ns
5
ns
4
ns
tsk(p)
tt
Pulse skew, |tPHL – tPLH|
ten
tdis
Enable time, control inputs to active output
70
ns
Disable time, control inputs to high-impedance output
80
ns
tPHZ
tPLZ
Propagation delay time, high-level to high-impedance output
80
ns
70
ns
tPZH
tPZL
Propagation delay time, high-impedance to high-level output
70
ns
70
ns
Transition time (tr or tf)
See Figure 4
Propagation delay time, low-level to high-impedance output
See Figures 7 and 8
Propagation delay time, high-impedance to low-level output
2
ns
† All typical values are at VCC = 5 V, TA = 25°C.
NOTE 5. This parameter is applicable at one VCC and operating temperature within the recommended operating conditions and to any two
devices.
10
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
PARAMETER MEASUREMENT INFORMATION
SN75976A = 5 V
SN55976A = 4.5 V
A
S1
B+
IO
15 pF
II
A
Input
(see Note A)
165 Ω
B
165 Ω
375 Ω
VO
VI
375 Ω
75 Ω
VOD
IO
B–
S2
VO
†
15 pF
† CDE0 and DE/RE are at 2 V, BSR is at 0.8 V and, for the SN75976A only, all others are open.
‡ For the SN75976A only, all nine drivers are enabled, similarly loaded, and switching.
Figure 1. Driver Test Circuit, Currents, and Voltages‡
3V
Input
1.5 V
1.5 V
0V
tPLH
Output, VOD
tPHL
0V
10%
90%
90%
tr
VOD(H)
0V
10%
S1 to A or B
VOD(L)
tf
Figure 2. Driver Delay and Transition Time Test Waveforms
Generator
(see Note A)
Input B +
50 Ω
IO
VID
Generator
(see Note A)
50 Ω
Output
Input B –
VO
CL = 15 pF
†
† CDE0, CDE1, CDE2, BSR, CRE, and DE/RE at 0.8 V
‡ For the SN75976A only, all nine receivers are enabled and switching.
Figure 3. Receiver Propagation Delay and Transition Time Test Circuit‡
NOTES: A. All input pulses are supplied by a generator having the following characteristics: tr ≤ 6 ns, tf ≤ 6 ns, PRR ≤ 1 MHz, duty cycle = 50%,
ZO = 50 Ω.
B. All resistances are in Ω and ± 5%, unless otherwise indicated.
C. All capacitances are in pF and ± 10%, unless otherwise indicated.
D. All indicated voltages are ± 10 mV.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
11
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
PARAMETER MEASUREMENT INFORMATION
3V
Input B –
1.5 V
1.5 V
Input B +
0V
tPLH
Output
tPHL
90%
1.4 V
10%
90%
tr
VOH
1.4 V
10%
VOL
tf
Figure 4. Receiver Delay and Transition Time Waveforms
4.5 V
A
S1
B+
50 pF
A
0 V or 3 V
165 Ω
B
165 Ω
375 Ω
75 Ω
VOD
375 Ω
B–
DE/RE
S2
50 pF†
See Table 1
Input
† Includes probe and jig capacitance in two places.
Figure 5. Driver Enable and Disable Time Test Circuit
Table 1. Enabling For Driver Enable And Disable Time
DRIVER
BSR
CDE0
CDE1
CDE2
CRE
1–8
H
H
L
L
X
9
L
H
H
H
H
3V
Input, DE/RE
1.5 V
1.5 V
0V
tPZH
tPHZ
VOD(H)
Output, VOD
0V
0V
∼ –1 V
tPZL
tPLZ
∼1V
Output, VOD
A at 3V
S1 to B
0V
0V
VOD(L)
A at 0V
S1 to A
Figure 6. Driver Enable Time Waveforms
NOTES: A. All input pulses are supplied by a generator having the following characteristics: tr ≤ 6 ns, tf ≤ 6 ns, PRR ≤ 1 MHz, duty cycle = 50%,
ZO = 50 Ω.
B. All resistances are in Ω and ± 5%, unless otherwise indicated.
C. All capacitances are in pF and ± 10%, unless otherwise indicated.
D. All indicated voltages are ± 10 mV.
12
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
PARAMETER MEASUREMENT INFORMATION
VT
0 V or 3 V
Input
3 V or 0 V
620 Ω
B+
A
Output
DE/RE
†
40 pF‡
B–
† CDE0 is high, CDE1, CDE2, BSR, and CRE are low and, for
the SN75976A only, all others are open.
‡ Includes probe and jig capacitance.
Figure 7. Receiver Enable and Disable Time Test Circuit
3V
Input
1.4 V
1.4 V
0V
tPLZ
Output
tPZL
1.4 V
VOD
1.4 V
Indeterminate
tPHZ
Output
VOD
B + at 0 V
B – at 3 V
VT = VCC
tPZH
1.4 V
1.4 V
B + at 3 V
B – at 0 V
VT = 0
Indeterminate
Figure 8. Receiver Enable and Disable Time Waveforms
NOTES: A. All input pulses are supplied by a generator having the following characteristics: tr ≤ 6 ns, tf ≤ 6 ns, PRR ≤ 1 MHz, duty cycle = 50%,
ZO = 50 Ω.
B. All resistances are in Ω and ± 5%, unless otherwise indicated.
C. All capacitances are in pF and ± 10%, unless otherwise indicated.
D. All indicated voltages are ± 10 mV.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
13
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
TYPICAL CHARACTERISTICS
AVERAGE SUPPLY CURRENT
vs
FREQUENCY
LOGIC INPUT CURRENT
vs
INPUT VOLTAGE
– 30
A, DE/RE,CRE,BSR
– 25
200
I I – Logic Input Current – µ A
I CC – Average Supply Current – mA
250
150
100
ÁÁ
ÁÁ
ÁÁ
9 Drivers
50
– 20
– 15
– 10
–5
9 Receivers
0
0.001
0.01
0.1
1
10
0
100
0
1
f – Frequency – MHz
Figure 9
BUS
DRIVER
INPUT CURRENT
vs
INPUT VOLTAGE
LOW-LEVEL OUTPUT VOLTAGE
vs
LOW-LEVEL OUTPUT CURRENT
VOL – Low-Level Output Voltage – V
I I – Input Current – mA
5
2.5
10
5
0
ÁÁ
ÁÁ
–5
– 15
– 10
–5
0
5
10
15
20
2
1.5
1
0.5
0
0
10
VI – Input Voltage – V
20
30
40
50
Figure 12
POST OFFICE BOX 655303
60
70
80
90 100
IOL – Low-Level Output Current – mA
Figure 11
14
4
Figure 10
15
– 10
– 20
2
3
VI – Input Voltage – V
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
TYPICAL CHARACTERISTICS
DRIVER
DRIVER
HIGH-LEVEL OUTPUT VOLTAGE
vs
HIGH-LEVEL OUTPUT CURRENT
AVERAGE DIFFERENTIAL OUTPUT VOLTAGE
vs
AVERAGE CASE TEMPERATURE
|VOD | – Average Differential Output Voltage – V
4
VOH – High-Level Output Voltage – V
3.5
ÁÁ
ÁÁ
ÁÁ
3
2.5
2
1.5
1
0.5
0
0
– 20
– 40
– 60
– 80
IOH – High-Level Output Current – mA
– 100
2.5
VOD(L), VCC = 5.25 V
2
1.5
VOD(L), VCC = 4.75 V
1
VOD(H), VCC = 5.25 V
ÁÁ
ÁÁ
ÁÁ
VOD(H), VCC = 4.75 V
0.5
S1 to Position B (see Figure 1)
0
0
40
60
100
20
80
120
TC – Average Case Temperature – °C
140
Figure 14
Figure 13
RECEIVER
DRIVER
PROPAGATION DELAY TIME
vs
CASE TEMPERATURE
PROPAGATION DELAY TIME
vs
CASE TEMPERATURE
16
14
14
tPHL(max)
t pd – Propagation Delay Time – ns
t pd – Propagation Delay Time – ns
VCC = 5 V,
S1 to Position B (see Figure 1)
tPLH(max)
12
tPHL(min)
10
tPLH(min)
8
6
(Data Extracted From 7 Wafer Lots)
4
12
tPHL(max)
10
8
tPLH(max)
6
tPLH(min)
tPHL(min)
4
2
VCC = 5 V
Data Extracted From 7 Wafer Lots
2
0
0
20
40
60
80
100
120
140
0
20
TC – Case Temperature – °C
40
60
80
100
120
140
TC – Case Temperature – °C
Figure 15
Figure 16
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
15
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
TYPICAL CHARACTERISTICS
DRIVER
OUTPUT CURRENT
vs
SUPPLY VOLTAGE
100
TA = 25°C
80
I O – Output Current – mA
IOH
60
40
20
0
– 20
– 40
– 60
IOL
– 80
0
1
2
3
4
VCC – Supply Voltage – V
Figure 17
16
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
5
6
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
Table 2. Typical Signal and Terminal Assignments
SCSI CONTROL
IPI DATA
CDE0
SIGNAL
TERMINAL
54
DIFFSENSE
SCSI DATA
DIFFSENSE
CDE1
55
GND
GND
VCC
XMTA, XMTB
VCC
GND
IPI CONTROL
CDE2
56
GND
GND
XMTA, XMTB
SLAVE/MASTER
BSR
2
GND
GND
GND, BSR
GND
CRE
3
GND
GND
GND
1A
4
DB0, DB8
ATN
AD7, BD7
VCC
NOT USED
1DE/RE
5
DBE0, DBE8
INIT EN
GND
GND
2A
6
DB1, DB9
BSY
AD6, BD6
NOT USED
2DE/RE
7
DBE1, DBE9
BSY EN
GND
GND
3A
8
DB2, DB10
ACK
AD5, BD5
SYNC IN
9
3DE/RE
DBE2, DBE10
INIT EN
GND
GND
10
DB3, DB11
RST
AD4, BD4
SLAVE IN
4DE/RE
11
DBE3, DBE11
GND
GND
GND
5A
19
DB4, DB12
MSG
AD3, BD3
NOT USED
5DE/RE
20
DBE4, DBE12
TARG EN
GND
GND
6A
21
DB5, DB13
SEL
AD2, BD2
SYNC OUT
6DE/RE
22
DBE5, DBE13
SEL EN
GND
GND
7A
23
DB6, DB14
C/D
AD1, BD1
MASTER OUT
7DE/RE
24
DBE6, DBE14
TARG EN
GND
GND
8A
25
DB7, DB15
REQ
AD0, BD0
SELECT OUT
8DE/RE
26
DBE7, DBE15
TARG EN
GND
GND
9A
27
DBP0, DBP1
I/O
AP, BP
ATTENTION IN
9DE/RE
28
DBPE0, DBPE1
TARG EN
XMTA, XMTB
VCC
4A
ABBREVIATIONS:
DBn = data bit n, where n = (0,1, . . . ,15)
DBEn = data bit n enable, where n = (0,1, . . . ,15)
DBP0 = parity bit for data bits 0 through 7 or IPI bus A
DBPE0 = parity bit enable for P0
DBP1 = parity bit for data bits 8 through 15 or IPI bus B
DBPE1 = parity bit enable for P1
ADn or BDn = IPI Bus A – Bit n (ADn) or Bus B – Bit n (BDn), where n = (0,1, . . . ,7)
AP or BP = IPI parity bit for bus A or bus B
XMTA or XMTB = transmit enable for IPI bus A or B
BSR = bit significant response
INIT EN = common enable for SCSI initiator mode
TARG EN = common enable for SCSI target mode
NOTE A: Signal inputs are shown as active high. When only active-low inputs are available, logic inversion
is accomplished by reversing the B + and B – connector terminal assignments.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
17
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
Function Tables
RECEIVER
DRIVER
B+
A
INPUTS
B+
A
B–
B–
B +†
B –†
OUTPUT
A
INPUT
A
L
H
H
L
L
H
L
H
TRANSCEIVER
OUTPUTS
B+
B–
L
H
H
L
DRIVER WITH ENABLE
B+
A
B+
B–
A
B–
DE/RE
DE/RE
DE/RE
L
L
H
H
INPUTS
A B +†
–
–
L
H
L
H
–
–
B –†
A
H
L
–
–
L
H
–
–
INPUTS
DE/RE
A
OUTPUTS
B–
B+
–
–
L
H
L
L
H
H
–
–
H
L
WIRED-OR DRIVER
L
H
L
H
OUTPUTS
B–
B+
Z
Z
L
H
Z
Z
H
L
TWO-ENABLE INPUT DRIVER
B+
A
A
B–
B+
B–
DE/RE
INPUT
A
L
H
INPUTS
DE/RE A
OUTPUTS
B+
B–
Z
H
L
L
H
H
Z
L
L
H
L
H
OUTPUTS
B–
B+
Z
H
L
H
Z
L
H
L
H = high level, L = low level, X = irrelevant, Z = high impedance (off)
† An H in this column represents a voltage of 200 mV or higher than the other bus input. An L represents a voltage of 200 mV or lower than the
other bus input. Any voltage less than 200 mV results in an indeterminate receiver output.
18
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
VCC
VCC
SCSI
Connector
620 Ω †
nB +
nA
I/O
EN
620 Ω †
+
nB –
–
SCSI
Connector
620 Ω †
nB +
nA
I
(b) ACTIVE-LOW BIDIRECTIONAL I/O
WITH SEPARATE ENABLE
VCC
VCC
620 Ω †
620 Ω †
I
+
nB –
O
–
–
nDE/RE
(d) SEPARATE ACTIVE-HIGH INPUT, OUTPUT,
AND ENABLE
VCC
VCC
SCSI
Connector
nB +
nA
+
nB –
EN
(c) WIRED-OR DRIVER AND ACTIVE-HIGH INPUT
I
O‡
SCSI
Connector
nB +
nA
O‡
nDE/RE
620 Ω †
+
nDE/RE
(a) ACTIVE-HIGH BIDIRECTIONAL I/O
WITH SEPARATE ENABLE
VCC
–
nB –
EN
nDE/RE
nB +
nA
I/O
SCSI
Connector
nB –
SCSI
Connector
620 Ω †
–
+
EN
nDE/RE
nA
I
nB +
nB –
O
–
+
nDE/RE
620 Ω
(e) SEPARATE ACTIVE-LOW INPUT AND
OUTPUT AND ACTIVE-HIGH ENABLE
(f) WIRED-OR DRIVER AND ACTIVE-LOW INPUT
† When 0 is open drain
‡ Must be open-drain or 3-state output
NOTE A: The BSR, CRE, A, and DE/RE inputs have internal pullup resistors. CDE0, CDE1, and CDE2 have internal pulldown resistors.
Figure 18. Typical SCSI Transceiver Connections
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
19
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
channel logic configurations with control input logic
The following logic diagrams show the positive-logic representation for all combinations of control inputs. The
control inputs are from MSB to LSB; the BSR, CDE0, CDE1, CDE2, and CRE bit values are shown below the
diagrams. Channel 1 is at the top of the logic diagrams; channel 9 is at the bottom of the logic diagrams.
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Figure 19. 00000
20
Hi-Z
Figure 20. 00001
Figure 21. 00010
POST OFFICE BOX 655303
Figure 22. 00011
• DALLAS, TEXAS 75265
Figure 23. 00100
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Figure 24. 00101
Hi-Z
Figure 25. 00110
Figure 26. 00111
Figure 28. 01001
Figure 27. 01000
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
21
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
Figure 32. 01101
Figure 29. 01010
22
Figure 30. 01011
Figure 31. 01100
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
Figure 33. 01110
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Figure 34. 01111
Figure 35.
10000
and 10001
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Figure 36. 10010
and 10011
Figure 37. 10100
and 10101
Hi-Z
Figure 38. 10110
and 10111
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
23
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
APPLICATION INFORMATION
Hi-Z
Figure 39. 11000
and 11001
Hi-Z
Figure 40. 11010
and 11011
Hi-Z
Figure 41. 11100
and 11101
Hi-Z
Figure 42. 11110
and 11111
24
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
MECHANICAL INFORMATION
DGG (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
48 PIN SHOWN
PINS **
48
56
64
A MAX
12,60
14,10
17,10
A MIN
12,40
13,90
16,90
DIM
0,27
0,17
0,50
48
0,08 M
25
6,20
6,00
8,30
7,90
0,15 NOM
1
Gage Plane
24
A
0,25
0°– 8°
0,75
0,50
Seating Plane
1,20 MAX
0,05 MIN
0,10
4040078 / D 08/96
NOTES: B. All linear dimensions are in millimeters.
C. This drawing is subject to change without notice.
D. Falls within JEDEC MO-153
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
25
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
MECHANICAL INFORMATION
DL (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
48 PIN SHOWN
PINS **
28
48
56
A MAX
0.380
(9,65)
0.630
(16,00)
0.730
(18,54)
A MIN
0.370
(9,40)
0.620
(15,75)
0.720
(18,29)
DIM
0.025 (0,635)
0.012 (0,305)
0.008 (0,203)
48
0.005 (0,13) M
25
0.006 (0,15) NOM
0.299 (7,59)
0.291 (7,39)
0.420 (10,67)
0.395 (10,03)
Gage Plane
0.010 (0,25)
1
0°– 8°
24
0.040 (1,02)
A
0.020 (0,51)
Seating Plane
0.110 (2,79) MAX
0.008 (0,20) MIN
0.004 (0,10)
4040048 / B 02/95
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion not to exceed 0.006 (0,15).
26
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
MECHANICAL INFORMATION
WD (R-GDFP-F**)
CERAMIC DUAL FLATPACK
48 PIN SHOWN
NO. OF
PINS**
0.120 (3,05)
0.075 (1,91)
A
MIN
MAX
48
0.630
(16,00)
0.730
(18,54)
56
0.610
(15,49)
0.710
(18,03)
0.005 (0,13) NOM
1.200 (30,50)
0.950 (24,13)
0.390 (9,91)
0.370 (9,40)
1
48
0.025 (0,635)
A
0.010 (0,25) TYP
24
25
4040176 / C 04/96
NOTES: A.
B.
C.
D.
E.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
This package can be hermetically sealed with a ceramic lid using glass frit.
Index point is provided on cap for pin identification only
Falls within MIL-STD-1835: GDFP1-F48 and JEDEC MO -146AA
GDFP1-F56 and JEDEC MO -146AB
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
27
PACKAGE OPTION ADDENDUM
www.ti.com
14-Oct-2022
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)
Samples
(4/5)
(6)
5962-9689301QXA
ACTIVE
CFP
WD
56
1
Non-RoHS
& Green
SNPB
N / A for Pkg Type
-55 to 125
5962-9689301QX
A
SNJ55976A1WD
SN55976A1WD
ACTIVE
CFP
WD
56
1
Non-RoHS
& Green
SNPB
N / A for Pkg Type
-55 to 125
SN55976A1WD
Samples
SN75976A1DGG
ACTIVE
TSSOP
DGG
56
35
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
SN75976A1
Samples
SN75976A1DL
ACTIVE
SSOP
DL
56
20
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
SN75976A1
Samples
SN75976A1DLR
ACTIVE
SSOP
DL
56
1000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
SN75976A1
Samples
SN75976A2DGG
ACTIVE
TSSOP
DGG
56
35
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
SN75976A2
Samples
SN75976A2DGGR
ACTIVE
TSSOP
DGG
56
2000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
SN75976A2
Samples
SN75976A2DL
ACTIVE
SSOP
DL
56
20
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
SN75976A2
Samples
SN75976A2DLR
ACTIVE
SSOP
DL
56
1000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
SN75976A2
Samples
SNJ55976A1WD
ACTIVE
CFP
WD
56
1
Non-RoHS
& Green
SNPB
N / A for Pkg Type
0 to 70
-55 to 125
5962-9689301QX
A
SNJ55976A1WD
(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
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