Texas Instruments SN74LVC157ADBR

Overview

SN74LVC157ADBR from Texas Instruments is a quadruple 2-line to 1-line data selector/multiplexer in SSOP-16 package, operating from 1.65V to 3.6V with ±24mA output drive, 5.2ns max propagation delay at 3.3V, and 5.5V-tolerant inputs. It enables signal routing in digital logic systems such as bus arbitration, data path selection, and address decoding in industrial microcontroller interfaces.

For engineers reviewing the SN74LVC157ADBR datasheet, SN74LVC157ADBR pinout, SN74LVC157ADBR application, or SN74LVC157ADBR equivalent, key selection criteria include its 16-pin SSOP footprint, active-low strobe (G) control, true-output logic, 3.3V/5V mixed-voltage compatibility, and –40°C to 125°C industrial temperature rating.

Technical Context

The SN74LVC157ADBR implements four independent 2:1 multiplexers sharing a common active-low strobe (G) and address select (A/B) input. When G is high, all outputs (1Y–4Y) are forced low; when G is low, each Y output reflects either the A or B input based on the A/B state.

Its CMOS design supports 5.5V-tolerant inputs while operating on 1.65V–3.6V V_CC, enabling level translation between 3.3V logic and legacy 5V peripherals. Output switching is characterized down to 1.8V supply with t_pd ≤ 6.4ns (typical) at 3.3V, and it meets JESD 17 latch-up (>250mA) and JESD 22 ESD standards (2kV HBM, 1kV CDM).

Key Specifications

Pinout & Package

SN74LVC157ADBR uses a 16-pin SSOP (Shrink Small Outline Package) with 0.635mm pitch, body size 6.20mm × 5.30mm, and nominal package size 6.20mm × 7.8mm. Thermal performance: R_θJA = 82°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2:1 multiplexer applications.

Compared with SN74LVC157ADR and 74LVC157APW, the SN74LVC157ADBR offers superior thermal resistance (82°C/W vs. 118.1°C/W and 141.8°C/W) and smaller footprint than SOIC, making it optimal for thermally demanding, high-density industrial PCBs.

Availability

SN74LVC157ADBR is available at Aetrix Electronics and suitable for industrial automation, automotive electronics, and embedded test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LVC157ADBR 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions, with decades of heritage in high-reliability logic families.

The SN74LVC157ADBR belongs to TI's LVC (Low-Voltage CMOS) logic series, designed specifically for low-voltage, high-speed, mixed-signal system interfacing in industrial, automotive, and communications infrastructure.

FAQ

What is the maximum clock/data rate supported by SN74LVC157ADBR?

The SN74LVC157ADBR is not a clocked device but a combinational multiplexer. Its maximum usable data rate depends on propagation delay and load capacitance. With t_pd ≤ 5.2ns at 3.3V and typical C_pd = 16pF, it reliably handles data transitions up to ~100MHz in well-terminated, low-capacitance circuits. For SN74LVC157ADBR, ensure input rise/fall times meet Δt/Δv ≤ 10ns/V specification to avoid timing violations.

Can SN74LVC157ADBR interface directly with 5V microcontrollers?

Yes - the SN74LVC157ADBR features 5.5V-tolerant inputs, allowing direct connection to 5V CMOS/TTL outputs without level-shifting circuitry. Its V_CC must remain within 1.65V–3.6V, so it operates as a 3.3V device receiving 5V signals. Outputs swing rail-to-rail (0V to V_CC), so downstream 5V logic requires pull-up resistors or compatible 3.3V-tolerant inputs. This behavior is fully specified for SN74LVC157ADBR in TI's SCAS292S datasheet.

What is the function of the G (strobe) pin on SN74LVC157ADBR?

The G pin on SN74LVC157ADBR is an active-low output enable/strobe. When G = HIGH, all four Y outputs (1Y–4Y) are forced LOW regardless of A/B or input states - providing simultaneous disable capability. When G = LOW, the multiplexer functions normally, routing either A or B inputs to Y outputs based on the A/B select line. This enables bus isolation, power sequencing control, and fault-safe shutdown in SN74LVC157ADBR-based systems.

Does SN74LVC157ADBR require external pull-up or pull-down resistors on unused inputs?

Yes - all unused inputs on SN74LVC157ADBR must be terminated to V_CC or GND to prevent floating nodes, which cause increased ICC, noise susceptibility, and potential logic contention. TI's SCAS292S explicitly states this requirement in Sections 4.3 and 4.4. For example, if only two of four channels are used, tie unused 3A/3B/4A/4B and 3Y/4Y (if left unconnected) to defined logic levels. Leaving inputs floating violates SN74LVC157ADBR's recommended operating conditions and may lead to erratic behavior.

Is SN74LVC157ADBR RoHS compliant and lead-free?

Yes - SN74LVC157ADBR is RoHS compliant and features NiPdAu (NIPDAU) lead finish, as confirmed in TI's PACKAGE OPTION ADDENDUM (July 2026). It carries MSL Level-1 (260°C, unlimited floor life) and is rated for reflow soldering per JEDEC J-STD-020. The part marking "LC157A" and packaging (2000-piece large tape-and-reel) align with TI's standard RoHS-compliant production release for SN74LVC157ADBR.