鈥?/div>
OEAB
LEAB
A1
GND
A2
A3
V
CC
(3.3 V)
A4
A5
A6
GND
A7
A8
A9
A10
A11
A12
GND
A13
A14
A15
V
CC
(3.3 V)
A16
A17
GND
A18
OEBA
LEBA
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
CEAB
CLKAB
B1
GND
B2
B3
V
CC
(5 V)
B4
B5
B6
GND
B7
B8
B9
B10
B11
B12
GND
B13
B14
B15
V
REF
B16
B17
GND
B18
CLKBA
CEBA
DESCRIPTION/ORDERING INFORMATION
The 'GTL16612 devices are 18-bit UBT鈩?transceivers that provide LVTTL-to-GTL/GTL+ and
GTL/GTL+-to-LVTTL signal-level translation. They combine D-type flip-flops and D-type latches to allow for
transparent, latched, clocked, and clock-enabled modes of data transfer identical to the '16601 function. The
devices provide an interface between cards operating at LVTTL logic levels and a backplane operating at
GTL/GTL+ signal levels. Higher-speed operation is a direct result of the reduced output swing (<1 V), reduced
input threshold levels, and OEC鈩?circuitry.
The user has the flexibility of using these devices at either GTL (V
TT
= 1.2 V and V
REF
= 0.8 V) or the preferred
higher noise margin GTL+ (V
TT
= 1.5 V and V
REF
= 1 V) signal levels. GTL+ is the Texas Instruments derivative
of the Gunning Transceiver Logic (GTL) JEDEC standard JESD 8-3. The B port normally operates at GTL or
GTL+ signal levels, while the A-port and control inputs are compatible with LVTTL logic levels and are 5-V
tolerant. V
REF
is the reference input voltage for the B port.
V
CC
(5 V) supplies the internal and GTL circuitry while V
CC
(3.3 V) supplies the LVTTL output buffers.
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.
Widebus, UBT, OEC are trademarks of Texas Instruments.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright 漏 1994鈥?005, Texas Instruments Incorporated
On products compliant to MIL-PRF-38535, all parameters are
tested unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.