74VMEH22501ADGGRE4

Universal Bus Functions Overview

The SN74VMEH22501ADGGRE4 is an 8-bit universal bus transceiver with two integrated 1-bit three-wire bus transceivers, designed for 3.3-V VCC operation with 5-V tolerant inputs. It supports transparent, latched, and flip-flop modes via D-type latches and flip-flops. The device features a split LVTTL port providing feedback paths for control and diagnostics monitoring. B-port outputs deliver high drive currents of -48 mA/64 mA, while Y and A-port outputs provide -12 mA/12 mA. It includes OEC circuitry to improve signal integrity and reduce EMI, and complies with VME64, 2eVME, and 2eSST protocols.

Universal Bus Functions Feature Summary

• Combines D-type latches and D-type flip-flops for flexible data-path operation in transparent, latched, or clocked modes.
• Provides separate LVTTL input and output ports on the bus transceivers to enable feedback paths for control and diagnostics monitoring.
• Supports live-insertion applications through Ioff, power-up 3-state, and BIAS VCC circuitry to prevent backflow current and driver conflicts.
• Features active bus-hold circuitry on 3A-port data inputs to maintain valid logic states for unused or undriven lines.

Universal Bus Functions Applications

• High-speed interface between cards operating at LVTTL logic levels and VME64, VME64x, or VME320 backplane topologies
• Systems requiring compliance with VME64, 2eVME, and 2eSST protocols
• Applications necessitating live insertion capabilities with precharge and post-discharge protection

Universal Bus Functions Procurement Notes

Verify that the ordering suffix 'E4' corresponds to the specific tape-and-reel packaging configuration for the DGG package as listed in the manufacturer's ordering information. Confirm that the component meets the RoHS standard and lead-free requirements specified in the production data documentation. Ensure the supply voltage range aligns with the recommended operating conditions of 3.15 V to 3.45 V for proper functionality.

Universal Bus Functions Selection Notes

Select this component when a single device must replace multiple standard logic functions such as transceivers, buffers, latches, and flip-flops. It is suitable for designs requiring high-drive outputs for large capacitive loads and noise immunity through pseudo-ETL input thresholds. Consider its compatibility with TTL and 5-V CMOS inputs if interfacing with mixed-voltage systems.

Universal Bus Functions Part Context

This device belongs to the Texas Instruments Widebus Family, specifically the UBT Transceiver series. It is pin-for-pin compatible with the SN74VMEH22501 but offers an extended operating temperature range from -40°C to 85°C. The SN74VMEH22501A integrates advanced OEC circuitry optimized for VME64x backplane models to enhance performance in distributed-load environments.

Universal Bus Functions Replacement Considerations

The SN74VMEH22501A can functionally replace standard logic devices including '245, '623, '645 transceivers; '241, '244, '541 buffers/drivers; '543 latched transceivers; '373, '573 latches; '646, '652 registered transceivers; and '374, '574 flip-flops within an 8-bit architecture.