TI SN65LVDS95DGG

SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
D
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DGG PACKAGE
(TOP VIEW)
21:3 Data Channel Compression at up to
1.36 Gigabits per Second Throughput
Suited for Point-to-Point Subsystem
Communication With Very Low EMI
21 Data Channels Plus Clock in
Low-Voltage TTL and 3 Data Channels Plus
Clock Out Low-Voltage Differential
Operates From a Single 3.3-V Supply and
250 mW (Typ)
5-V Tolerant Data Inputs
’LVDS95 Has Rising Clock Edge Triggered
Inputs
Bus Pins Tolerate 6-kV HBM ESD
Packaged in Thin Shrink Small-Outline
Package With 20 Mil Terminal Pitch
Consumes <1 mW When Disabled
Wide Phase-Lock Input Frequency Range
20 MHz to 65 MHz
No External Components Required for PLL
Inputs Meet or Exceed the Requirements of
ANSI EIA/TIA-644 Standard
Industrial Temperature Qualified
TA = – 40°C to 85°C
Replacement for the National DS90CR215
D4
VCC
D5
D6
GND
D7
D8
VCC
D9
D10
GND
D11
D12
VCC
D13
D14
GND
D15
D16
D17
VCC
D18
D19
GND
1
48
2
47
3
46
4
45
5
44
6
43
7
42
8
41
9
40
10
39
11
38
12
37
13
36
14
35
15
34
16
33
17
32
18
31
19
30
20
29
21
28
22
27
23
26
24
25
D3
D2
GND
D1
D0
NC
LVDSGND
Y0M
Y0P
Y1M
Y1P
LVDSVCC
LVDSGND
Y2M
Y2P
CLKOUTM
CLKOUTP
LVDSGND
PLLGND
PLLVCC
PLLGND
SHTDN
CLKIN
D20
description
The SN65LVDS95 LVDS serdes (serializer/deserializer) transmitter contains three 7-bit parallel-load serial-out
shift registers, a 7× clock synthesizer, and four low-voltage differential signaling (LVDS) line drivers in a single
integrated circuit. These functions allow 21 bits of single-ended LVTTL data to be synchronously transmitted
over 4 balanced-pair conductors for receipt by a compatible receiver, such as the SN65LVDS96.
When transmitting, data bits D0 through D20 are each loaded into registers of the SN65LVDS95 on the rising
edge of the input clock signal (CLKIN). The frequency of CLKIN is multiplied seven times and then used to
serially unload the data registers in 7-bit slices. The three serial streams and a phase-locked clock (CLKOUT)
are then output to LVDS output drivers. The frequency of CLKOUT is the same as the input clock, CLKIN.
The SN65LVDS95 requires no external components and little or no control. The data bus appears the same
at the input to the transmitter and output of the receiver with data transmission transparent to the user(s). The
only user intervention is the possible use of the shutdown/clear (SHTDN) active-low input to inhibit the clock
and shut off the LVDS output drivers for lower power consumption. A low level on this signal clears all internal
registers to a low level.
The SN65LVDS95 is characterized for operation over ambient air temperatures of – 40°C to 85°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  2000, 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.
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1
SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
functional block diagram
D0–6
D7–13
D14–20
7
7
7
Parallel-Load 7-Bit
Shift Register
A,B, ...G
Serial/LOAD
CLK
Parallel-Load 7-Bit
Shift Register
A,B, ...G
Serial/LOAD
CLK
Parallel-Load 7-Bit
Shift Register
A,B, ...G
Serial/LOAD
CLK
Y0P
Y0M
Y1P
Y1M
Y2P
Y2M
Control Logic
SHTDN
CLKIN
2
7× Clock/PLL
7×CLK
CLK
CLKINH
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CLKOUTP
CLKOUTM
SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
Dn
CLKIN
’LVDS95
CLKOUT
Previous Cycle
Current Cycle
Y0
Next
D6
D5
D4
D3
D2
D1
D0
D6+1
D13
D12
D11
D10
D9
D8
D7
D13+1
D20
D19
D18
D17
D16
D15
D14
D20+1
D0-1
Y1
D7-1
Y2
D14-1
Figure 1. ’LVDS95 Load and Shift Sequences
equivalent input and output schematic diagrams
VCC
VCC
D or
SHTDN
50 Ω
10 kΩ
50 Ω
YnP or
YnM
7V
7V
300 kΩ
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SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
absolute maximum ratings over operating free-air temperature (unless otherwise noted)†
Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 4 V
Voltage range at any output terminal, VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to VCC + 0.5 V
Voltage range at any input terminal, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 5.5 V
Electrostatic discharge (see Note 2): Bus pins (Class 3A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 KV
Bus pins (Class 2B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 V
All pins (Class 3A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 KV
All pins (Class 2B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 V
Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (see Dissipation Rating Table)
Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 40°C to 85°C
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 rating is measured using MIL-STD-883C Method, 3015.7.
DISSIPATION RATING TABLE
PACKAGE
TA ≤ 25°C
POWER RATING
DERATING FACTOR‡
ABOVE TA = 25°C
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
DGG
1316 mW
13.1 mW/°C
724 mW
526 mW
‡ This is the inverse of the junction-to-ambient thermal resistance when board-mounted and with no air flow.
recommended operating conditions
MIN
NOM
MAX
Supply voltage, VCC
3
3.3
3.6
High-level input voltage, VIH
2
Low-level input voltage, VIL
Operating free-air temperature, TA
4
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V
V
0.8
Differential load impedance, ZL
UNIT
V
90
132
Ω
– 40
85
°C
SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
electrical characteristics over recommended operating conditions (unless otherwise noted)
PARAMETER
TEST CONDITIONS
VIT
|VOD|
Input voltage threshold
∆|VOD|
Change in the steady-state differential output
voltage magnitude between opposite binary states
VOC(SS)
VOC(PP)
Steady-state common-mode output voltage
IIH
IIL
High-level input current
IOS
Short circuit output current
Short-circuit
IOZ
High-impedance state output current
ICC(AVG)
MIN
TYP†
MAX
1.4
Differential steady-state output voltage magnitude
Peak-to-peak common-mode output voltage
247
RL = 100 Ω,
50
1.125
1.375
80
V
mV
20
µA
±10
µA
VOY = 0 V
VOD = 0 V
±24
mA
±12
mA
VO = 0 V to VCC
±10
µA
Disabled, all inputs at GND
280
µA
110
mA
Enabled, RL = 100 Ω (4 places),
Worst-case pattern (see Figure 4),
tc = 15.38 ns
Quiescent current (average)
mV
150
VIH = VCC
VIL = 0 V
Low-level input current
V
454
See Figure 3
See Figure 3
UNIT
85
Ci
Input capacitance
† All typical values are VCC = 3.3 V, TA = 25°C.
3
pF
timing requirements
MIN
NOM
tc
tc
tw
Input clock period
15.4
High-level input clock pulse width duration
0.4tc
tt
tsu
Input signal transition time
th
Data hold time, D0 through D27 after CLKIN↑ (’95) (see Figure 2)
Data setup time, D0 through D27 before CLKIN↑ (’95) (see Figure 2)
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MAX
UNIT
50
ns
0.6tc
5
ns
ns
3
ns
1.5
ns
5
SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
switching characteristics over recommended operating conditions (unless otherwise noted)
PARAMETER
Delay time, CLKOUT serial bit position 0
t2
t3
Delay time, CLKOUT↑ serial bit position 2
t4
t5
Delay time, CLKOUT↑ serial bit position 4
t6
tsk(o)
Delay time, CLKOUT↑ serial bit position 6
Delay time, CLKOUT↑ serial bit position 1
Delay time, CLKOUT↑ serial bit position 3
tc = 15.38 ns (±0.2%),
|Input clock jitter| < 50 ps‡,
See Figure 5
Delay time, CLKOUT↑ serial bit position 5
TYP†
MAX
UNIT
0
0.20
ns
1/7tc–0.20
2/7tc–0.20
1/7tc+0.20
2/7tc+0.20
ns
3/7tc–0.20
4/7tc–0.20
3/7tc+0.20
4/7tc+0.20
ns
5/7tc–0.20
6/7tc–0.20
5/7tc+0.20
6/7tc+0.20
ns
–0.20
0.20
ns
Output skew, tn –n/7 tc
t7
Delay time, CLKIN↑ to CLKOUT↑
∆tC(O)
tw
tt
MIN
–0.20
TEST CONDITIONS
t0
t1
Output clock cycle-to-cycle
cycle to cycle jitter§
ns
ns
tc = 15.38 ns (±0.2%),
|Input clock jitter| < 50 ps‡,
See Figure 5
4.2
ns
tc = 15.38 ns + 0.75 sin(2π500E3t)
±0.05 ns, See Figure 6
±80
ps
±300
ps
tc = 15.38 ns + 0.75 sin(2π2E6t)
±0.05 ns, See Figure 6
High-level output clock pulse duration
4/7 tc
Differential output voltage transition time (tr or tf)
ns
See Figure 3
260
ns
700
1500
ten
Enable time, SHTDN↑ to phase lock (Yn valid)
See Figure 7
1
tdis
Disable time, SHTDN↓ to off-state (CLKOUT low) See Figure 8
250
† All typical values are VCC = 3.3 V, TA = 25°C.
‡ |Input clock jitter| is the magnitude of the change in the input clock period.
§ The output clock jitter is the change in the output clock period from one cycle to the next cycle observed over 15,000 cycles.
ps
ms
ns
PARAMETER MEASUREMENT INFORMATION
Dn
ÉÉÉÉÉÉ
ÉÉÉÉÉÉ
tsu
th
ÉÉÉÉ
ÉÉÉÉ
CLKIN
CLKSEL HIGH
NOTE: All input timing is defined at 1.4 V on an input signal with a 10% to 90% rise or fall time of less than 5 ns.
Figure 2. Setup and Hold Time Definition
6
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SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
PARAMETER MEASUREMENT INFORMATION
49.9 Ω ±1%
(2 Places)
YP
VID
YM
CL = 10 pF MAX
(2 Places)
VOC
NOTE: The lumped instrumentation capacitance for any single ended voltage
measurement is less than or equal to 10 pF. When making measurements
at YP or YM, the complementary output shall be similarly loaded.
100%
80%
VOD(H)
0V
VOD(L)
20%
0%
tr
tf
VOC(PP)
VOC(SS)
VOC(SS)
0V
Figure 3. Test Load and Voltage Definitions for LVDS Outputs
VIH = 2 V and VIL = 0.8 V
T
CLKIN
EVEN Dn
ODD Dn
Figure 4. Worst-Case‡ Power Test Pattern
‡ The worst-case test pattern produces nearly the maximum switching frequency for all of the LV-TTL outputs.
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SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
PARAMETER MEASUREMENT INFORMATION
t7
CLKIN
CLKOUT
t6
t5
t4
t3
t2
t1
t0
Yn
t7
VOD(H)
CLKIN
1.4 V
0V
CLKOUT
or Xn
VOD(L)
t0–t6
Figure 5. Timing Definitions
Reference
+
Σ
Device
Under
Test
VCO
+
Modulation
v(t) = A sin(2πfmodt)
HP8656B Signal
Generator,
0.1 MHz–990 MHz
RF Output
HP8665A Synthesized
Signal Generator,
0.1 MHz–4200 MHz
Modulation Input
Output
Device Under
Test
CLKIN
CLKOUT
Figure 6. Clock Jitter Test Setup
8
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DTS2070C
Digital Time
Scope
Input
SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
PARAMETER MEASUREMENT INFORMATION
CLKIN
Dn
ten
SHTDN
Invalid
Yn
Valid
Figure 7. Enable Time Measurement Definition
CLKIN
tdis
SHTDN
CLKOUT
Figure 8. Disable Time Measurement Definition
TYPICAL CHARACTERISTICS
WORST-CASE SUPPLY CURRENT
vs
FREQUENCY
100
I CC – Supply Current – mA
VCC = 3.6 V
ÁÁ
ÁÁ
80
60
VCC = 3 V
VCC = 3.3 V
40
20
0
30
40
50
60
f – Frequency – MHz
70
Figure 9
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SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
APPLICATION INFORMATION
16-bit bus extension
In a 16-bit bus application (Figure 10), TTL data and clock coming from bus transceivers that interface the
backplane bus arrive at the Tx parallel inputs of the LVDS serdes transmitter. The clock associated with the bus
is also connected to the device. The on-chip PLL synchronizes this clock with the parallel data at the input. The
data is then multiplexed into three different line drivers which perform the TTL to LVDS conversion. The clock
is also converted to LVDS and presented to a separate driver. This synchronized LVDS data and clock at the
receiver, which recovers the LVDS data and clock, performs a conversion back to TTL. Data is then
demultiplexed into a parallel format. An on-chip PLL synchronizes the received clock with the parallel data, and
then all are presented to the parallel output port of the receiver.
16-Bit
BTL Bus
Interface
SN74FB2032
SN74FB2032
CLK
TTL
Interface
LVDS
Interface
0 To 10 Meters
(Media Dependent)
SN65LVDS95
SN65LVDS96
TTL
Interface
D0–D7 8
8
D8–D15 8
8 D8–D15
D0–D7
16-Bit
BTL Bus
Interface
SN74FB2032
SN74FB2032
XMIT Clock
RCV Clock
CLK
Backplane
Bus
Backplane
Bus
Figure 10. 16-Bit Bus Extension
16-bit bus extension with parity
In the previous application we did not have a checking bit that would provide assurance that the data crosses
the link. If we add a parity bit to the previous example, we would have a diagram similar to the one in Figure 11.
The device following the SN74FB2032 is a low cost parity generator. Each transmit-side transceiver/parity
generator takes the LVTTL data from the corresponding transceiver, performs a parity calculation over the byte,
and then passes the bits with its calculated parity value on the parallel input of the LVDS serdes transmitter.
Again, the on-chip PLL synchronizes this transmit clock with the eighteen parallel bits (16 data + 2 parity) at the
input. The synchronized LVDS data/parity and clock arrive at the receiver.
The receiver performs the conversion from LVDS to LVTTL and the transceiver/parity generator performs the
parity calculations. These devices compare their corresponding input bytes with the value received on the parity
bit. The transceiver/parity generator will assert its parity error output if a mismatch is detected.
10
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SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
APPLICATION INFORMATION
16-Bit
BTL Bus
Interface
LVDS
Interface
0 To 10 Meters
(Media Dependent)
TTL
Interface
W/Parity
TTL
Interface
SN65LVDS95
SN74FB2032
9 Bit Latchable
Transceiver/ With
Parity Generator
8
Parity
Parity
8
D8–D15
SN74FB2032
9 Bit Latchable
Transceiver/ With
Parity Generator
TTL
Interface
16-Bit
BTL Bus
Interface
SN65LVDS96
8
D0–D7
TTL
Interface
W/Parity
D0–D7
9 Bit Latchable
Transceiver/ With
Parity Generator
8
Parity
Parity
SN74FB2032
D8–D15
9 Bit Latchable
Transceiver/ With
Parity Generator
SN74FB2032
Parity
Error
CLK
XMIT Clock
CLK
RCV Clock
Backplane
Bus
Backplane
Bus
Figure 11. 16-Bit Bus Extension With Parity
low cost virtual backplane transceiver
Figure 12 represents LVDS serdes in an application as a virtual backplane transceiver (VBT). The concept of
a VBT can be achieved by implementing individual LVDS serdes chipsets in both directions of subsystem
serialized links.
Depending on the application, the designer will face varying choices when implementing a VBT. In addition to
the devices shown in Figure 12, functions such as parity and delay lines for control signals could be included.
Using additional circuitry, half-duplex or full-duplex operation can be achieved by configuring the clock and
control lines properly.
The designer may choose to implement an independent clock oscillator at each end of the link and then use
a PLL to synchronize LVDS serdes’s parallel I/O to the backplane bus. Resynchronizing FIFOs may also be
required.
Bus
Transceivers
LVDS Serdes
Transmitter
TTL
Inputs
Up To
21 or 28
Bits
Backplane
Bus
Bus
Transceivers
LVDS Serdes
Receiver
TTL
Outputs
Up To
21 or 28
Bits
LVDS
Serial Links
4 or 5
Pairs
LVDS Serdes
Transmitter
Bus
Transceivers
LVDS Serdes
Receiver
Backplane
Bus
Bus
Transceivers
Figure 12. Virtual Backplane Transceiver
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SN65LVDS95
LVDS SERDES TRANSMITTER
SLLS297F – MAY 1998 – REVISED FEBRUARY 2000
MECHANICAL DATA
DGG (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
48 PIN SHOWN
0,27
0,17
0,50
48
0,08 M
25
6,20
6,00
8,30
7,90
0,15 NOM
Gage Plane
1
0,25
24
0°– 8°
A
0,75
0,50
Seating Plane
0,15
0,05
1,20 MAX
PINS **
0,10
48
56
64
A MAX
12,60
14,10
17,10
A MIN
12,40
13,90
16,90
DIM
4040078 / F 12/97
NOTES: A.
B.
C.
D.
12
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Body dimensions do not include mold protrusion not to exceed 0,15.
Falls within JEDEC MO-153
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IMPORTANT NOTICE
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any product or service without notice, and advise customers to obtain the latest version of relevant information
to verify, before placing orders, that information being relied on is current and complete. All products are sold
subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those
pertaining to warranty, patent infringement, and limitation of liability.
TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily
performed, except those mandated by government requirements.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF
DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL
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In order to minimize risks associated with the customer’s applications, adequate design and operating
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TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent
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Copyright  2000, Texas Instruments Incorporated