Diodes Incorporated 74LVCH245AT20-13

Overview

74LVCH245AT20-13 from Diodes Incorporated is an octal bus transceiver with bus hold and 3-state outputs, designed for bidirectional asynchronous data transfer between A and B buses in mixed-voltage systems. It operates from 1.65V to 3.6V, tolerates 5.5V inputs, supports partial power-down via IOFF, and delivers ±24mA drive at VCC = 3.0V - used in notebook I/O expansion and peripheral bus isolation.

For engineers reviewing the 74LVCH245AT20-13 datasheet, 74LVCH245AT20-13 pinout, 74LVCH245AT20-13 application, or 74LVCH245AT20-13 equivalent, key selection criteria include voltage translation capability (1.65–3.6V supply with 5.5V-tolerant inputs), bus hold functionality eliminating external resistors, IOFF-enabled isolation during power-down, and TSSOP-20 thermal performance (θJA = 74°C/W).

Technical Context

This device implements dual-directional 8-bit data routing controlled by DIR and OE pins: DIR selects A→B or B→A flow, while OE enables/disables all outputs into high-impedance state. Bus hold circuitry actively maintains logic levels on unused inputs without pull resistors, reducing board space and signal integrity risk.

IOFF protection disables output drivers when VCC = 0V, preventing back-current damage during partial power-down sequences. Schmitt-trigger inputs ensure noise immunity across voltage rails, and ESD ratings exceed 2kV HBM, 1kV CDM, and 200V MM per JESD22.

Key Specifications

Pinout & Package

TSSOP-20 package: 6.4mm × 6.5mm × 1.2mm body, 0.65mm lead pitch, exposed pad not present. RoHS-compliant, halogen-free "Green" construction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal bus transceiver applications.

Compared with SN74LVC245AQPWRQ1 and 74LVC245ABQ,215, the 74LVCH245AT20-13 offers optimal balance of industrial temperature range (-40°C to +125°C), proven TSSOP-20 manufacturability, and integrated bus hold - making it the default choice for cost-sensitive, high-volume consumer and industrial embedded systems where automotive qualification or extreme miniaturization are unnecessary.

Availability

74LVCH245AT20-13 is available at Aetrix Electronics and suitable for PC notebook I/O expansion, hard disk drive interface isolation, and set-top box HDMI CEC bus extension requiring stable component supply and long-term lifecycle support.

Supply support for 74LVCH245AT20-13 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability, energy-efficient components for computing, industrial, and consumer markets.

The 74LVCH245A belongs to Diodes' LVC logic family - engineered for low-voltage mixed-signal interfacing with emphasis on voltage translation, bus integrity, and power-down safety in portable and embedded systems.

FAQ

Can the 74LVCH245AT20-13 operate with VCC = 1.5V?

No. The recommended minimum supply voltage is 1.65V per datasheet Section 6. Absolute operation below 1.65V risks undefined logic behavior, increased propagation delay variability, and potential bus hold failure. Data retention mode (1.5V) applies only to static storage - not active transceiver operation.

Does the bus hold feature work when OE = HIGH?

Yes. Bus hold circuitry remains fully active regardless of OE state - it functions on all A/B and Y/X pins whenever VCC is powered, preserving logic levels even when outputs are disabled. This eliminates floating inputs during system initialization or fault conditions.

What is the maximum capacitive load this device can drive reliably?

Based on switching characteristics and output drive specs, the device supports ≤50pF load capacitance while maintaining tPD ≤9.2ns and VOL ≤0.55V at VCC = 3.0V and IOL = 24mA. Exceeding 50pF increases delay and degrades edge rate, requiring layout optimization or buffer staging.

Is thermal pad connection required for the TSSOP-20 package?

No. The TSSOP-20 variant (T20) has no exposed thermal pad - thermal dissipation relies on leads and PCB copper. Unlike the QFN-20 version, no solder paste or thermal via design is needed; standard TSSOP reflow profiles apply without modification.