SN74GTLPH16945

활성

16비트 LVTTL-GTLP 버스 트랜시버

제품 상세 정보

Technology family GTLP Applications GTL Rating Catalog Operating temperature range (°C) -40 to 85
Technology family GTLP Applications GTL Rating Catalog Operating temperature range (°C) -40 to 85
TSSOP (DGG) 48 101.25 mm² 12.5 x 8.1
  • Member of the Texas Instruments Widebus™ Family
  • 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

OEC, TI-OPC, and Widebus are trademarks of Texas Instruments.

  • Member of the Texas Instruments Widebus™ Family
  • 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

OEC, TI-OPC, and Widebus are trademarks of Texas Instruments.

The SN74GTLPH16945 is a medium-drive, 16-bit bus transceiver that provides LVTTL-to-GTLP and GTLP-to-LVTTL signal-level translation. It is partitioned as two 8-bit transceivers. 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 .

GTLP is the Texas Instruments derivative of the Gunning Transceiver Logic (GTL) JEDEC standard JESD 8-3. The ac specification of the SN74GTLPH16945 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.

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.

The SN74GTLPH16945 is a medium-drive, 16-bit bus transceiver that provides LVTTL-to-GTLP and GTLP-to-LVTTL signal-level translation. It is partitioned as two 8-bit transceivers. 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 .

GTLP is the Texas Instruments derivative of the Gunning Transceiver Logic (GTL) JEDEC standard JESD 8-3. The ac specification of the SN74GTLPH16945 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.

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.

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기술 자료

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유형 직함 날짜
* Data sheet 16-Bit LVTTL-to-GTLP Bus Transceiver datasheet (Rev. D) 2001/11/29
Application note Schematic Checklist - A Guide to Designing with Auto-Bidirectional Translators PDF | HTML 2024/07/12
Application note Understanding Transient Drive Strength vs. DC Drive Strength in Level-Shifters (Rev. A) PDF | HTML 2024/07/03
Selection guide Voltage Translation Buying Guide (Rev. A) 2021/04/15
Selection guide Logic Guide (Rev. AB) 2017/06/12
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) 2015/12/02
User guide LOGIC Pocket Data Book (Rev. B) 2007/01/16
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection 2004/07/08
Application note TI IBIS File Creation, Validation, and Distribution Processes 2002/08/29
Application note Power-Up 3-State (PU3S) Circuits in TI Standard Logic Devices 2002/05/10
Application note Logic in Live-Insertion Applications With a Focus on GTLP 2002/01/14
User guide GTLP/GTL Logic High-Performance Backplane Drivers Data Book (Rev. A) 2001/09/15
Application note Achieving Maximum Speed on Parallel Buses With Gunning Transceiver Logic (GTLP) 2001/04/05
Selection guide Advanced Bus Interface Logic Selection Guide 2001/01/09
Application brief Texas Instruments GTLP Frequently Asked Questions 2001/01/01
Application note Fast GTLP Backplanes With the GTLPH1655 (Rev. A) 2000/09/19
More literature High Level Brochure of Gunning Transceiver Logic Plus 2000/01/14

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TSSOP (DGG) 48 Ultra Librarian

주문 및 품질

포함된 정보:
  • RoHS
  • REACH
  • 디바이스 마킹
  • 납 마감/볼 재질
  • MSL 등급/피크 리플로우
  • MTBF/FIT 예측
  • 물질 성분
  • 인증 요약
  • 지속적인 신뢰성 모니터링
포함된 정보:
  • 팹 위치
  • 조립 위치

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