The SN74VMEH22501A-EP 8-bit universal bus transceiver has two integral 1-bit three-wire bus transceivers and is designed for 3.3-V VCC operation with 5-V tolerant inputs. The UBT transceiver allows transparent, latched, and flip-flop modes of data transfer, and the separate LVTTL input and outputs on the bus transceivers provide a feedback path for control and diagnostics monitoring. This device provides a high-speed interface between cards operating at LVTTL logic levels and VME64, VME64x, or VME320(2) backplane topologies.
The SN74VMEH22501A-EP device is pin-for-pin compatible to the SN74VMEH22501 device (SCES357), but operates at a wider operating temperature range.
High-speed backplane operation is a direct result of the improved OEC circuitry and high drive that has been designed and tested into the VME64x backplane model. The B-port I/Os are optimized for driving large capacitive loads and include pseudo-ETL input thresholds (½ VCC ±50 mV) for increased noise immunity. These specifications support the 2eVME protocols in VME64x (ANSI/VITA 1.1) and 2eSST protocols in VITA 1.5.
With proper design of a 21-slot VME system, a designer can achieve 320-MB transfer rates on linear backplanes and, possibly, 1-GB transfer rates on the VME320 backplane.
All inputs and outputs are 5-V tolerant and are compatible with TTL and 5-V CMOS inputs.
Active bus-hold circuitry holds unused or undriven 3A-port inputs at a valid logic state. Bus-hold circuitry is not provided on 1A or 2A inputs, any B-port input, or any control input. Use of pullup or pulldown resistors with the bus-hold circuitry is not recommended.
This device is fully specified for live-insertion applications using Ioff, power-up 3-state, and BIAS VCC. The Ioff circuitry prevents damaging current to backflow through the device when it is powered off/on. 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.
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, output-enable (OE and OEBY) inputs should be tied to VCC through a pullup resistor and output-enable (OEAB) inputs should be tied to GND through a pulldown resistor; the minimum value of the resistor is determined by the drive capability of the device connected to this input.
| Type | Title | Date | ||
|---|---|---|---|---|
| * | Data sheet | SN74VMEH22501A-EP 8-Bit Universal Bus Transceiver and Two 1-Bit Bus Transceivers With Split LVTTL Port, Feedback Path, and 3-State Outputs datasheet (Rev. A) | PDF | HTML | 09 Nov 2015 |
| * | VID | SN74VMEH22501A-EP VID V6205606 | 21 Jun 2016 | |
| * | Radiation & reliability report | CVMEH22501AIDGVREP Reliability Report | 04 Jun 2012 | |
| Selection guide | Logic Guide (Rev. AB) | 12 Jun 2017 | ||
| Application note | Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) | 02 Dec 2015 | ||
| User guide | LOGIC Pocket Data Book (Rev. B) | 16 Jan 2007 | ||
| Application note | Semiconductor Packing Material Electrostatic Discharge (ESD) Protection | 08 Jul 2004 | ||
| Application note | SN74VMEH22501 Universal Bus Transceiver for the VMEbus Backplane | 14 May 2003 | ||
| More literature | SN74VMEH22501 Application Clip | 04 Mar 2003 | ||
| Application note | VMEH22501 in 2eSST and Conventional VME Backplane Applications | 07 Oct 2002 | ||
| Application note | Power-Up 3-State (PU3S) Circuits in TI Standard Logic Devices | 10 May 2002 |
For additional terms or required resources, click any title below to view the detail page where available.
| Package | Pins | Download |
|---|---|---|
| TSSOP (DGG) | 48 | View options |
| TVSOP (DGV) | 48 | View options |
Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.
If you have questions about quality, packaging or ordering TI products, see TI support.