T7256 Agere Systems, T7256 Datasheet - Page 27

• Manufacturer Part Number: T7256
• Description: (T7234 - T7256) Compliance
• Manufacturer: Agere Systems

Lucent Technologies Inc.
February 1998
Application Briefs
T7234 Reference Circuit
Table 5. T7234 Reference Schematic Parts List (continued)
1. Kemet is a registered trademark of Kemet Laboratories Company, Inc.
2. Philips is a registered trademark of Philips Manufacturing Company.
3. Vitramon is a registered trademark of Vitramon, Inc.
4. Hewlett Packard is a registered trademark of Hewlett-Packard Company.
5. Polyswitch is a registered trademark of Raychem Corporation.
6. Bel and Bel Fuse are registered trademarks of Bel Fuse, Inc.
7. Molex is a registered trademark of Molex, Inc.
8. Pulse Engineering is a registered trademark of Pulse Engineering, Inc.
9. Dale is a registered trademark of Dale Electronics, Inc.
10. Valor is a registered trademark of Valor Electronics, Inc.
11. Advanced Power Components is a registered trademark of Advanced Power Technology, Inc.
12. Vacuumschmelze is a registered trademark of Vacuumschmelze GmbH.
13. SGS-Thomson is a registered trademark of SGS-Thomson Microelectronics, Inc.
14. Teccor is a registered trademark of Teccor, Inc.
15.MTRON is a registered trademark of MTRON Industries, Inc., a wholly owned subsidiary of Lynch* Corporation.
*
Note:
Table 6. Line-Side Resistor Requirements
Designator
Lynch is a registered trademark of Lynch Corporation.
Reference
Lucent 2754H2
Lucent 2754K2
VR[3,4]
Lucent 2809A
Valor PT4084
Transformer
VR1
VR2
The Lucent 2754K2 and the Valor PT4084 have different winding resistances than the Lucent 2754H2, and therefore require a change
to the line-side resistor (R15). In addition, if the Bel Fuse is used in place of the Raychem TR600-150 PTC at location F1 (which will
sacrifice the resettable protection that the PTC provides), the line-side resistors must be adjusted to compensate for reduced resistance
due to the removal of the PTC (12 ). The following table lists the necessary resistor values for these cases. Note that R15 is specified
at 1%. This is due to the fact that the values were chosen from standard 1% resistor tables. When a PTC is used, the overall tolerance
will be greater than 1%. This is acceptable, as long as the total line-side resistance is kept as close as possible to the ideal value. See
Questions and Answers section, #6 for more details.
X1
Transient Voltage
Suppressor
Transient Voltage
Suppressor
Transient Voltage
Suppressor, 6.8 V
15.36 Crystal
When Raychem TR600-150 Is Used
Description
(continued)
(continued)
15.4
9.53
21
R13
0
T7234 Single-Chip NT1 (SCNT1) Euro-LITE Transceiver
SGS-
Thomson
SGS-
Thomson
Motorola
Saronix
[phone]
Source
13
When Bel Fuse Is Used
SM6T6V8CA
Alternates:
Motorola SA6.5CA, P6KE6.8CA, P6KE7.5CA
SMP100-140
Alternate:
Teccor
1.5SMC6.8AT3
Alternate:
Motorola 1N6269A
SRX5144
Alternates:
MTRON
2B Elettronica S.D.L. TP0648 39-6-6622432
14
33.2
27.4
21.5
10.7
15
P1602AB [phone]
R13
4044-001 [phone]
Part #
23