TI SN74GTLPH16912

SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
D
D
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D
D
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D
D
D
D
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D
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DGG OR DGV PACKAGE
(TOP VIEW)
Member of Texas Instruments’ Widebus
Family
UBT Transceiver Combines D-Type
Latches and D-Type Flip-Flops for
Operation in Transparent, Latched,
Clocked, and Clock-Enabled Modes
TI-OPC Circuitry Limits Ringing on
Unevenly Loaded Backplanes
OEC Circuitry Improves Signal Integrity
and Reduces Electromagnetic Interference
Bidirectional Interface Between GTLP
Signal Levels and LVTTL Logic Levels
LVTTL Interfaces Are 5-V Tolerant
Medium-Drive GTLP Outputs (50 mA)
LVTTL Outputs (–24 mA/24 mA)
GTLP Rise and Fall Times Designed for
Optimal Data-Transfer Rate and Signal
Integrity in Distributed Loads
Ioff, Power-Up 3-State, and BIAS VCC
Support Live Insertion
Bus Hold on A-Port Data Inputs
Distributed VCC and GND Pins Minimize
High-Speed Switching Noise
Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
ESD Protection Exceeds JESD 22
– 2000-V Human-Body Model (A114-A)
– 200-V Machine Model (A115-A)
– 1000-V Charged-Device Model (C101)
OEAB
LEAB
A1
GND
A2
A3
VCC
A4
A5
A6
GND
A7
A8
A9
A10
A11
A12
GND
A13
A14
A15
VCC
A16
A17
GND
A18
OEBA
LEBA
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
23
34
24
33
25
32
26
31
27
30
28
29
CEAB
CLKAB
B1
GND
B2
B3
BIAS VCC
B4
B5
B6
GND
B7
B8
B9
B10
B11
B12
GND
B13
B14
B15
VREF
B16
B17
GND
B18
CLKBA
CEBA
description
The SN74GTLPH16912 is a medium-drive, 18-bit UBT transceiver that provides LVTTL-to-GTLP and
GTLP-to-LVTTL signal-level translation. It allows for transparent, latched, clocked, and clock-enabled modes
of data transfer. The device provides a high-speed interface between cards operating at LVTTL logic levels and
a backplane operating at GTLP signal levels. High-speed (about three times faster than standard TTL or LVTTL)
backplane operation is a direct result of GTLP’s reduced output swing (<1 V), reduced input threshold levels,
improved differential input, OEC circuitry, and TI-OPC circuitry. Improved GTLP OEC and TI-OPC circuits
minimize bus-settling time and have been designed and tested using several backplane models. The medium
drive allows incident-wave switching in heavily loaded backplanes with equivalent load impedance down
to 19 Ω.
GTLP is the Texas Instruments (TI) derivative of the Gunning Transceiver Logic (GTL) JEDEC standard
JESD 8-3. The ac specification of the SN74GTLPH16912 is given only at the preferred higher noise-margin
GTLP, but the user has the flexibility of using this device at either GTL (VTT = 1.2 V and VREF = 0.8 V) or GTLP
(VTT = 1.5 V and VREF = 1 V) signal levels.
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.
OEC, TI, TI-OPC, UBT, and Widebus are trademarks of Texas Instruments.
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.
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1
SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
description (continued)
Normally, the B port operates at GTLP signal levels. The A-port and control inputs operate at LVTTL logic levels,
but are 5-V tolerant and are compatible with TTL and 5-V CMOS inputs. VREF is the B-port differential input
reference voltage.
This device is fully specified for live-insertion applications using Ioff, power-up 3-state, and BIAS VCC. The Ioff
circuitry disables the outputs, preventing damaging current backflow through the device when it is powered
down. The power-up 3-state circuitry places the outputs in the high-impedance state during power up and power
down, which prevents driver conflict. The BIAS VCC circuitry precharges and preconditions the B-port
input/output connections, preventing disturbance of active data on the backplane during card insertion or
removal, and permits true live-insertion capability.
This GTLP device features TI-OPC circuitry, which actively limits overshoot caused by improperly terminated
backplanes, unevenly distributed cards, or empty slots during low-to-high signal transitions. This improves
signal integrity, which allows adequate noise margin to be maintained at higher frequencies.
Active bus-hold circuitry holds unused or undriven LVTTL data inputs at a valid logic state. Use of pullup or
pulldown resistors with the bus-hold circuitry is not recommended.
When VCC is between 0 and 1.5 V, the device is in the high-impedance state during power up or power down.
However, to ensure the high-impedance state above 1.5 V, the output-enable (OE) input should be tied to VCC
through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of
the driver.
ORDERING INFORMATION
TA
–40°C
40°C to 85°C
PACKAGE†
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
TSSOP – DGG
Tape and reel
SN74GTLPH16912GR
GTLPH16912
TVSOP – DGV
Tape and reel
SN74GTLPH16912VR
GL912
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design
guidelines are available at www.ti.com/sc/package.
2
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SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
functional description
The SN74GTLPH16912 is a medium-drive (50 mA), 18-bit UBT transceiver containing D-type latches and
D-type flip-flops for data-path operation in transparent, latched, clocked, or clock-enabled modes and can
replace any of the functions shown in Table 1. Data polarity is noninverting.
Table 1. SN74GTLPH16912 UBT Transceiver Replacement Functions
8 BIT
9 BIT
10 BIT
16 BIT
18 BIT
Transceiver
FUNCTION
’245, ’623, ’645
’863
’861
’16245, ’16623
’16863
Buffer/driver
’241, ’244, ’541
’827
’16241, ’16244, ’16541
’16825
’16543
’16472
’16373
’16843
’16646, ’16652
’16474
Latched transceiver
’543
Latch
’373, ’573
Registered transceiver
’646, ’652
Flip-flop
’374, ’574
’843
’841
’821
’16374
Standard UBT
’16500, ’16501
Universal bus driver
’16835
Registered transceiver with clock enable
’2952
Flip-flop with clock enable
’377
’16470, ’16952
’823
’16823
Standard UBT with clock enable
’16600, ’16601
SN74GTLPH16912 UBT transceiver replaces all above functions
Data flow in each direction is controlled by clock enables (CEAB and CEBA), latch enables (LEAB and LEBA),
clock (CLKAB and CLKBA), and output enables (OEAB and OEBA). CEAB and CEBA and OEAB and OEBA
control the 18 bits of data for the A-to-B and B-to-A directions, respectively.
For A-to-B data flow, when CEAB is low, the device operates on the low-to-high transition of CLKAB for the
flip-flop and on the high-to-low transition of LEAB for the latch path, i.e., if CEAB and LEAB are low, the A data
is latched, regardless of the state of CLKAB (high or low). If LEAB is high, the device is in transparent mode.
When OEAB is low, the outputs are active. When OEAB is high, the outputs are in the high-impedance state.
The data flow for B to A is similar to that of A to B, except CEBA, OEBA, LEBA, and CLKBA are used.
FUNCTION TABLE†
INPUTS
CEAB
OEAB
LEAB
CLKAB
A
OUTPUT
B
MODE
X
H
X
X
X
Z
Isolation
Latched storage of A data
L
L
L
H
X
L
L
L
L
X
B0‡
B0§
X
L
H
X
L
L
X
L
H
X
H
H
L
L
L
↑
L
L
L
L
L
↑
H
H
B0§
True transparent
Clocked storage of A data
H
L
L
X
X
Clock inhibit
† A-to-B data flow is shown. B-to-A data flow is similar, but uses CEBA, OEBA, LEBA, and
CLKBA. The condition when OEAB and OEBA are both low at the same time is not
recommended.
‡ Output level before the indicated steady-state input conditions were established, provided
that CLKAB was high before LEAB went low
§ Output level before the indicated steady-state input conditions were established
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3
SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
logic diagram (positive logic)
35
VREF
1
OEAB
CEAB
56
55
CLKAB
2
LEAB
28
LEBA
30
CLKBA
CEBA
29
27
OEBA
CE
1D
3
A1
C1
CLK
CE
1D
C1
CLK
To 17 Other Channels
4
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54
B1
SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC and BIAS VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 4.6 V
Input voltage range, VI (see Note 1): A-port and control inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V
B port and VREF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 4.6 V
Voltage range applied to any output in the high-impedance or power-off state, VO
(see Note 1): A port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V
B port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 4.6 V
Current into any output in the low state, IO: A port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 mA
B port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 mA
Current into any A port output in the high state, IO (see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 mA
Continuous current through each VCC or GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±100 mA
Input clamp current, IIK (VI < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –50 mA
Output clamp current, IOK (VO < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –50 mA
Package thermal impedance, θJA (see Note 3): DGG package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64°C/W
DGV package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48°C/W
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°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. The input and output negative-voltage ratings may be exceeded if the input and output clamp-current ratings are observed.
2. This current flows only when the output is in the high state and VO > VCC.
3. The package thermal impedance is calculated in accordance with JESD 51-7.
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SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
recommended operating conditions (see Notes 4 through 7)
VCC,
BIAS VCC
Supply voltage
VTT
Termination voltage
VREF
Reference voltage
VI
Input voltage
VIH
High level input voltage
High-level
VIL
Low level input voltage
Low-level
IIK
IOH
Input clamp current
Low level output current
Low-level
∆t/∆v
Input transition rise or fall rate
∆t/∆VCC
TA
Power-up ramp rate
NOM
MAX
UNIT
3.15
3.3
3.45
V
GTL
1.14
1.2
1.26
GTLP
1.35
1.5
1.65
GTL
0.74
0.8
0.87
GTLP
0.87
1
1.1
VCC
VTT
5.5
B port
Except B port
B port
Except B port
VREF+0.05
2
B port
V
V
V
V
VREF–0.05
0.8
V
–18
mA
A port
–24
mA
A port
24
B port
50
Except B port
High-level output current
IOL
MIN
Outputs enabled
10
–40
ns/V
µs/V
20
Operating free-air temperature
mA
85
°C
NOTES: 4. All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
5. Proper connection sequence for use of the B-port I/O precharge feature is GND and BIAS VCC = 3.3 V first, I/O second, and
VCC = 3.3 V last, because the BIAS VCC precharge circuitry is disabled when any VCC pin is connected. The control and VREF
inputs can be connected anytime, but normally are connected during the I/O stage. If B-port precharge is not required, any
connection sequence is acceptable, but generally, GND is connected first.
6. VTT and RTT can be adjusted to accommodate backplane impedances if the dc recommended IOL ratings are not exceeded.
7. VREF can be adjusted to optimize noise margins, but normally is two-thirds VTT. TI-OPC circuitry is enabled in the A-to-B direction
and is activated when VTT > 0.7 V above VREF. If operated in the A-to-B direction, VREF should be set to within 0.6 V of VTT to
minimize current drain.
6
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SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
electrical characteristics over recommended operating free-air temperature range for GTLP
(unless otherwise noted)
PARAMETER
VIK
VOH
A port
TEST CONDITIONS
VCC = 3.15 V,
VCC = 3.15 V to 3.45 V,
II = –18 mA
IOH = –100 µA
VCC = 3
3.15
15 V
IOH = –12 mA
IOH = –24 mA
VOL
B port
A-port and
control inputs
II‡
A port
IBHLO#
IBHHO||
A port
ICC
A port
A port
A or B port
Ci
Ciio
Control inputs
UNIT
–1.2
V
VCC–0.2
2.4
V
2
0.5
VCC = 3.15 V to 3.45 V,
IOL = 24 mA
IOL = 100 µA
0.2
VCC = 3.15 V
IOL = 10 mA
IOL = 40 mA
IOL = 50 mA
VI = 0 or VCC
0.55
VI = 5.5 V
VI = 0 to 1.5 V
±20
VCC = 3
3.15
15 V
VCC = 3.45 V
0.4
0.2
±10
75
µA
–75
µA
500
µA
VI = 0.8 V
VI = 2 V
VCC = 3.45 V,
VCC = 3.45 V,
VI = 0 to VCC
VI = 0 to VCC
VCC = 3.45 V, IO = 0,
VI (A-port or control input) = VCC or GND,
VI (B port) = VTT or GND
Outputs high
50
Outputs low
50
Outputs disabled
50
A port
B port
VO = 1.5 V or 0
µA
µ
±10
VCC = 3.15 V,
VCC = 3.15 V,
VI = 3.15 V or 0
VO = 3.15 V or 0
V
0.4
µA
–500
VCC = 3.45 V, One A-port or control input at VCC – 0.6 V,
Other A-port or control inputs at VCC or GND
∆ICCk
MAX
0.2
B port
IBHL§
IBHH¶
TYP†
IOL = 100 µA
IOL = 12 mA
VCC = 3.15 V to 3.45 V,
A port
MIN
mA
1.5
mA
4
5.5
pF
7
8.5
8.5
9.5
pF
† All typical values are at VCC = 3.3 V, TA = 25°C.
‡ For I/O ports, the parameter II includes the off-state output leakage current.
§ The bus-hold circuit can sink at least the minimum low sustaining current at VILmax. IBHL should be measured after lowering VIN to GND and
then raising it to VILmax.
¶ The bus-hold circuit can source at least the minimum high sustaining current at VIHmin. IBHH should be measured after raising VIN to VCC and
then lowering it to VIHmin.
# An external driver must source at least IBHLO to switch this node from low to high.
|| An external driver must sink at least IBHHO to switch this node from high to low.
k This is the increase in supply current for each input that is at the specified TTL voltage level rather than VCC or GND.
hot-insertion specifications for A port over recommended operating free-air temperature range
PARAMETER
TEST CONDITIONS
MIN
MAX
UNIT
10
µA
VO = 0.5 V to 3 V,
VI or VO = 0 to 5.5 V
OE = 0
±30
µA
VO = 0.5 V to 3 V,
OE = 0
±30
µA
Ioff
IOZPU
VCC = 0,
VCC = 0 to 1.5 V,
BIAS VCC = 0,
IOZPD
VCC = 1.5 V to 0,
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7
SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
live-insertion specifications for B port over recommended operating free-air temperature range
PARAMETER
TEST CONDITIONS
BIAS VCC = 0,
±30
µA
BIAS VCC = 0,
VO = 0.5 V to 1.5 V, OE = 0
±30
µA
BIAS VCC = 3
3.15
15 V to 3
3.45
45 V
V,
VO (B port) = 0 to 1.5
15V
BIAS VCC = 3.3 V,
IO = 0
VO (B port) = 0.6 V
IOZPD
VCC = 1.5 V to 0,
VCC = 0 to 3.15 V
VO
IO
VCC = 0,
UNIT
µA
BIAS VCC = 0,
VCC = 3.15 V to 3.45 V
VCC = 0,
MAX
10
VCC = 0,
VCC = 0 to 1.5 V,
ICC (BIAS VCC)
MIN
VI or VO = 0 to 1.5 V
VO = 0.5 V to 1.5 V, OE = 0
Ioff
IOZPU
BIAS VCC = 3.15 V to 3.45 V,
0.95
5
mA
10
µA
1.05
V
µA
–1
timing requirements over recommended ranges of supply voltage and operating free-air
temperature, VTT = 1.5 V and VREF = 1 V for GTLP (unless otherwise noted)
MIN
fclock
tw
tsu
th
8
Clock frequency
Pulse duration
Setup time
Hold time
POST OFFICE BOX 655303
LEAB or LEBA high
2.8
CLKAB or CLKBA high or low
2.8
A before CLKAB↑
1.8
B before CLKBA↑
1.5
A before LEAB↓
1
B before LEBA↓
2
CEAB before CLKAB↑
1.5
CEBA before CLKBA↑
1.4
A after CLKAB↑
0.3
B after CLKBA↑
0.4
A after LEAB↓
1.1
B after LEBA↓
0.4
CEAB after CLKAB↑
1
CEBA after CLKBA↑
1
• DALLAS, TEXAS 75265
MAX
UNIT
175
MHz
ns
ns
ns
SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature, VTT = 1.5 V and VREF = 1 V for GTLP (see Figure 1)
PARAMETER
fmax
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
ten
tdis
tr
tf
tPLH
FROM
(INPUT)
TO
(OUTPUT)
A
B
LEAB
B
CLKAB
B
OEAB
B
2.1
6
2.2
6.3
2.2
6.3
2.2
6.5
2.2
6.5
2
6.5
2
6.1
Fall time, B outputs (80% to 20%)
CLKBA
A
OEBA
tdis
† All typical values are at VCC = 3.3 V, TA = 25°C.
A
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
ns
ns
ns
ns
ns
2
A
UNIT
MHz
6
2.4
LEBA
tPHL
ten
MAX
2.1
Rise time, B outputs (20% to 80%)
A
tPHL
tPLH
TYP†
175
B
tPHL
tPLH
MIN
ns
1.8
5.8
1.8
5.8
0.4
5.3
0.4
5.3
.6
5.6
.6
5.7
0.3
6.2
0.3
5.9
ns
ns
ns
ns
9
SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
PARAMETER MEASUREMENT INFORMATION
1.5 V
6V
500 Ω
From Output
Under Test
S1
S1
Open
6V
GND
TEST
tPLH/tPHL
tPLZ/tPZL
tPHZ/tPZH
GND
CL = 50 pF
(see Note A)
25 Ω
Open
500 Ω
From Output
Under Test
Test
Point
CL = 30 pF
(see Note A)
LOAD CIRCUIT FOR B OUTPUTS
LOAD CIRCUIT FOR A OUTPUTS
tw
3V
3V
1.5 V
Input
1.5 V
Timing
Input
1.5 V
0V
0V
VOLTAGE WAVEFORMS
PULSE DURATION
tsu
th
VOH
Data
Input
VM
VM
0V
3V
Input
1.5 V
1.5 V
0V
tPLH
tPHL
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
(VM = 1.5 V for A port and 1 V for B port)
(VOH = 3 V for A port and 1.5 V for B port)
VOH
Output
1V
1V
3V
VOL
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
(A port to B port)
1V
1V
0V
tPLH
1.5 V
1.5 V
0V
Output
Waveform 1
S1 at 6 V
(see Note B)
tPLZ
3V
1.5 V
VOL + 0.3 V
VOL
tPHZ
tPZH
tPHL
VOH
Output
1.5 V
tPZL
1.5 V
Input
Output
Control
1.5 V
VOL
Output
Waveform 2
S1 at GND
(see Note B)
1.5 V
VOH
VOH – 0.3 V
≈0 V
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES
(A port)
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
(B port to A port)
NOTES: A. CL includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR ≈ 10 MHz, ZO = 50 Ω, tr ≈ 2 ns, tf ≈ 2 ns.
D. The outputs are measured one at a time with one transition per measurement.
Figure 1. Load Circuits and Voltage Waveforms
10
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SN74GTLPH16912
18-BIT LVTTL-TO-GTLP UNIVERSAL BUS TRANSCEIVER
SCES288C – OCTOBER 1999 – REVISED JULY 2001
DISTRIBUTED-LOAD BACKPLANE SWITCHING CHARACTERISTICS
The preceding switching characteristics table shows the switching characteristics of the device into a lumped load
(Figure 1). However, the designer’s backplane application probably is a distributed load. The physical representation
is shown in Figure 2. This backplane, or distributed load, can be approximated closely to a resistor inductance
capacitance (RLC) circuit, as shown in Figure 3. This device has been designed for optimum performance in this RLC
circuit. The following switching characteristics table shows the switching characteristics of the device into the RLC
load, to help the designer better understand the performance of the GTLP device in this typical backplane. See
www.ti.com/sc/gtlp for more information.
38 Ω
.25”
ZO = 70 Ω
2”
Conn.
1”
Conn.
Conn.
1”
1”
2”
38 Ω
1.5 V
1.5 V
.25”
1.5 V
19 Ω
Conn.
LL = 19 nH
From Output
Under Test
1”
Test
Point
CL = 9 pF
Rcvr
Rcvr
Rcvr
Slot 2
Slot 9
Slot 10
Drvr
Slot 1
Figure 2. Medium-Drive Test Backplane
Figure 3. Medium-Drive RLC Network
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature, VTT = 1.5 V and VREF = 1 V for GTLP (see Figure 3)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
tPLH
tPHL
A
B
tPLH
tPHL
LEAB
B
tPLH
tPHL
CLKAB
B
ten
tdis
OEAB
B
tr
tf
TYP†
4.5
4.5
4.7
4.7
4.7
4.7
4.8
4.4
UNIT
ns
ns
ns
ns
Rise time, B outputs (20% to 80%)
1.2
ns
Fall time, B outputs (80% to 20%)
† All typical values are at VCC = 3.3 V, TA = 25°C. All values are derived from TI-SPICE models.
2.5
ns
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11
MECHANICAL DATA
MPDS006C – FEBRUARY 1996 – REVISED AUGUST 2000
DGV (R-PDSO-G**)
PLASTIC SMALL-OUTLINE
24 PINS SHOWN
0,40
0,23
0,13
24
13
0,07 M
0,16 NOM
4,50
4,30
6,60
6,20
Gage Plane
0,25
0°–8°
1
0,75
0,50
12
A
Seating Plane
0,15
0,05
1,20 MAX
PINS **
0,08
14
16
20
24
38
48
56
A MAX
3,70
3,70
5,10
5,10
7,90
9,80
11,40
A MIN
3,50
3,50
4,90
4,90
7,70
9,60
11,20
DIM
4073251/E 08/00
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion, not to exceed 0,15 per side.
Falls within JEDEC: 24/48 Pins – MO-153
14/16/20/56 Pins – MO-194
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1
MECHANICAL DATA
MTSS003D – JANUARY 1995 – REVISED JANUARY 1998
DGG (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
48 PINS 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.
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
POST OFFICE BOX 655303
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1
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