Texas Instruments SN74LVC2G157YEAR

Overview

SN74LVC2G157YEAR from Texas Instruments is a single 2-line to 1-line data selector multiplexer designed for 1.65-V to 5.5-V V_CC operation, featuring true and complementary outputs (Y and Y), a common strobe input (G), and I_off support for partial-power-down applications. It delivers 6 ns max propagation delay at 3.3 V, ±24-mA output drive, and 5.5-V tolerant inputs - enabling level translation in embedded sensor interfaces and low-voltage MCU peripheral routing.

For engineers reviewing the SN74LVC2G157YEAR datasheet, SN74LVC2G157YEAR pinout, SN74LVC2G157YEAR application, or SN74LVC2G157YEAR equivalent, key selection criteria include its dual-output configuration, NanoFree™ DSBGA-8 package compatibility, I_off-enabled live insertion capability, and verified 1.65–5.5-V supply range with 5.5-V input tolerance - critical for mixed-voltage signal routing in space-constrained industrial and portable designs.

Technical Context

The SN74LVC2G157YEAR implements standard CMOS logic with balanced high-drive push-pull outputs and integrated negative clamping diodes on all I/Os. Its functional behavior is defined by a 3-input control matrix: G (strobe), A/B (select), and data inputs A and B - where G = HIGH forces both outputs to fixed states (Y = LOW, Y = HIGH), while G = LOW enables data routing based on A/B state.

It supports partial-power-down via I_off, disabling outputs when V_CC = 0 to prevent back-drive current, and operates across full industrial temperature (–40°C to +85°C) with JESD 78 Class II latch-up immunity (>100 mA) and 2000-V HBM ESD protection. The device is not a bus switch or analog mux - it performs digital signal selection only, with no internal termination or slew-rate control.

Key Specifications

Pinout & Package

SN74LVC2G157YEAR is packaged in an 8-pin DSBGA (YZP) measuring 1.91 mm × 0.91 mm with bottom-side ball layout - optimized for ultra-compact portable and wearable electronics. Pin functions are validated per TI SCES207N Rev N mechanical drawing and pin function table.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 2-to-1 digital multiplexer applications.

Compared with SN74LVC2G157YEAR, SN74LVC1G157DBVR sacrifices inverted output and package size for simpler integration, while NC7SZ157P5X trades I_off safety and dual outputs for marginal speed gain - making SN74LVC2G157YEAR the only option combining NanoFree™ miniaturization, true/complementary outputs, and certified partial-power-down capability.

Availability

SN74LVC2G157YEAR is available at Aetrix Electronics and suitable for industrial sensor hubs, portable medical devices, and wireless communication modules requiring stable component supply, long-term lifecycle assurance, and verified DSBGA-8 packaging compliance.

Supply support for SN74LVC2G157YEAR 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 over 50 years of innovation in high-reliability interface and signal-path components.

The SN74LVC2G157YEAR belongs to TI's LVC logic family - engineered for low-voltage, mixed-signal interoperability in space-constrained industrial and portable electronics, emphasizing voltage translation, power sequencing safety, and minimal board area.

FAQ

What is the function of the G (strobe) pin on the SN74LVC2G157YEAR?

The G pin is the common strobe input that globally enables or disables data routing. When G = HIGH, Y is forced LOW and Y is forced HIGH regardless of A/B or data inputs - effectively placing outputs in known states. When G = LOW, the SN74LVC2G157YEAR routes either A or B to Y/Y based on the A/B select signal. This behavior is explicitly defined in the Function Table of TI SCES207N Rev N.

Does the SN74LVC2G157YEAR support level translation, and how is it implemented?

Yes, the SN74LVC2G157YEAR supports down-translation: its inputs tolerate up to 5.5 V independent of V_CC, allowing 5-V sensor signals to be safely routed into 1.8-V or 3.3-V systems. This is achieved via internal negative clamping diodes and robust input structure - confirmed in Section 8.3.3 and Absolute Maximum Ratings of the official datasheet. The SN74LVC2G157YEAR does not perform up-translation.

Can unused inputs on the SN74LVC2G157YEAR be left floating?

No - all unused inputs (A, B, A/B, or G) must be terminated to V_CC or GND using a pull-up or pull-down resistor (typically 10 kΩ), as stated in Section 9.2.1.2 and TI application report SCBA004. Floating CMOS inputs cause undefined logic states, increased ICC, and potential oscillation due to slow edge rates - violating recommended operating conditions in SCES207N.

What is the significance of I_off in the SN74LVC2G157YEAR, and how does it affect system design?

I_off disables outputs when V_CC = 0, limiting leakage current to ±10 µA max. This prevents damaging back-current flow from live system buses into a powered-down SN74LVC2G157YEAR - essential for hot-pluggable modules, modular sensor nodes, and systems with staggered power sequencing. It is fully characterized per JESD 78 and verified in Electrical Characteristics tables.

Is the SN74LVC2G157YEAR pin-compatible with other packages in the same family, such as DCT or DCU?

No - the SN74LVC2G157YEAR (DSBGA-8, YZP) has a unique bottom-terminal ball layout incompatible with SSOP (DCT) or VSSOP (DCU) packages. Pin functions match across variants (A, B, A/B, G, Y, Y, V_CC, GND), but physical placement, solder mask, and thermal pad design differ fundamentally. Migration requires PCB redesign; see TI Mechanical Drawing SLZY022 for YZP dimensions.