Diodes Incorporated PI5C3257QEX-1516

Overview

PI5C3257QEX-1516 from Diodes Incorporated is a quad 2:1 analog multiplexer/demultiplexer bus switch with three-state outputs, pinout- and function-compatible with 74F257/74ALS257 logic families. It features 5Ω on-resistance, near-zero propagation delay (0.25 ns), ultra-low quiescent current (0.2 µA typical), and operates over –40°C to +85°C ambient. Used for high-speed data routing in notebook and embedded I/O expansion systems.

For engineers reviewing the PI5C3257QEX-1516 datasheet, PI5C3257QEX-1516 pinout, PI5C3257QEX-1516 application, or PI5C3257QEX-1516 equivalent, key selection criteria include on-resistance matching, propagation delay budget, enable/select timing margins, and QSOP-16 footprint compatibility with legacy 74-series logic layouts.

Technical Context

The PI5C3257QEX-1516 implements four independent bidirectional 2:1 analog switches controlled by a shared select (S) and enable (E) input. Each switch connects either IA/IB, IC/ID pair to YA/YB/YC/YD output with no internal logic buffering-preserving signal integrity and minimizing RC-induced delay.

Its architecture relies on low-threshold MOSFET pass gates optimized for 5V operation, delivering 5Ω R_ON at V_CC = 4.5V and 48mA test current. The device draws only 0.1–3.0 µA ICC across temperature, enabling battery-sensitive applications without compromising switching speed or noise immunity.

Key Specifications

Pinout & Package

PI5C3257QEX-1516 is packaged in a 16-pin QSOP (150-mil width), with 1.27 mm pitch and standard JEDEC MO-131 compliant footprint. Pin 1 is marked by a notch or dot; package thickness is 1.75 mm max.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3257PWR and 74LVC257PW, PI5C3257QEX-1516 uniquely balances 5V analog transparency, ultra-low standby power, and drop-in 74-series pin compatibility-making it optimal for mixed-voltage, battery-aware, and legacy-compatible designs.

Availability

PI5C3257QEX-1516 is available at Aetrix Electronics and suitable for notebook I/O expansion, industrial PLC backplane switching, embedded audio path selection, and test equipment signal multiplexing requiring stable component supply and long-term lifecycle support.

Supply support for PI5C3257QEX-1516 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 integrated circuits, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The PI5C3257 belongs to Diodes' Pericom® high-speed analog switch product line, engineered specifically for low-latency, low-power, and pin-compatible replacements of legacy 74-series logic in modern portable and industrial systems.

FAQ

What is the maximum capacitive load the PI5C3257QEX-1516 can drive while maintaining specified propagation delay?

The datasheet specifies t_IY = 0.25 ns with C_L = 50 pF and R_L = 500 Ω. At higher loads (e.g., 100 pF), delay increases linearly with RC time constant-measured as ~0.5 ns at 100 pF. For >100 pF loads, layout optimization (short traces, local decoupling) is required to maintain sub-nanosecond timing.

Can PI5C3257QEX-1516 safely interface between 3.3V and 5V logic domains?

Yes. Its absolute maximum ratings allow input/output voltages from –0.5 V to +7.0 V, and DC electrical characteristics are specified at V_CC = 5 V ±5%. When V_CC = 5 V, it reliably accepts 3.3V logic levels as valid VIH/VIL and drives 5V-tolerant receivers without level shifting.

Does the PI5C3257QEX-1516 require external pull-up or pull-down resistors on control pins?

No. The S and E inputs have CMOS-compatible thresholds (VIH = 2.0 V min, VIL = 0.8 V max) and negligible leakage (±1 µA). Direct connection to FPGA GPIO or microcontroller outputs is sufficient; external biasing is unnecessary unless noise immunity in high-EMI environments is required.

Is thermal derating required for continuous operation at 85°C ambient?

No derating is needed below 0.5 W total power dissipation. At max rated 120 mA output current and 5Ω R_ON, worst-case power per switch is 72 mW (I²R), well within the 0.5 W package limit. Junction temperature remains <105°C at 85°C ambient with standard 2-layer PCB copper area.