Diodes Incorporated PI4ULS3V502XVEX

Overview

PI4ULS3V502 from Diodes Incorporated (acquired Pericom Semiconductor) is a 2-bit bidirectional auto-sensing level translator for push-pull applications, supporting independent VCCA (0.85–2.7 V) and VCCB (1.35–3.6 V) rails, 280 Mb/s data rate at 2.5–3.6 V/1.8–2.7 V, 30 pF capacitive drive, and 2 kV system-level ESD rating - used in mobile phone baseband-to-PMIC voltage domain bridging.

For engineers reviewing the PI4ULS3V502 datasheet, PI4ULS3V502 pinout, PI4ULS3V502 application, or PI4ULS3V502 equivalent, key selection concerns include dual-supply rail independence, enable-controlled 3-state operation, bit-to-bit skew (<0.15 ns), overvoltage-tolerant I/O pins, and UDFN1.2×1.6-8L footprint compatibility with high-density portable PCBs.

Technical Context

The PI4ULS3V502 implements auto-sensing bidirectional translation using one-shot edge-detection circuits per channel, eliminating direction-control pins while enabling real-time signal flow arbitration between A and B ports. Each channel operates as either input or output depending on transient voltage transitions, with no static direction assignment required.

VCCA and VCCB supplies are fully decoupled: VCCA may be higher or lower than VCCB without restriction - unlike many competitors requiring VCCA ≤ VCCB − 0.4 V. The EN pin is referenced to VCCA and features overvoltage tolerance up to 3.6 V, allowing safe interfacing with higher-voltage control logic.

Key Specifications

Pinout & Package

Package: UDFN1.2×1.6-8L (1.2 mm × 1.6 mm, 0.4 mm pitch, exposed thermal pad).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bidirectional level translation applications.

Compared with TXS0102DCUR and SN74AVC2T244RSWR, the PI4ULS3V502 uniquely supports rail-flexible auto-sensing at 280 Mb/s with overvoltage-safe EN and zero-direction-pin operation - making it the only fit for high-density, multi-rail mobile SoC interconnects demanding timing-critical, sequenced-power resilience.

Availability

PI4ULS3V502XVEX is available at Aetrix Electronics and suitable for mobile phone baseband–PMIC bridging, eMMC/SDIO host interfaces, and wearable sensor hub interconnects requiring stable component supply across extended product lifecycles.

Supply support for PI4ULS3V502XVEX 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 acquired Pericom Semiconductor in 2017 and integrates its high-speed interface portfolio into broad analog and mixed-signal solutions for consumer, computing, and communications markets.

The PI4ULS3V502 belongs to Pericom's ULS (Ultra-Low Skew) level translator family, engineered specifically for timing-critical, multi-voltage domain bridging in space-constrained portable electronics.

FAQ

What is the minimum VCCA voltage supported for reliable operation?

The PI4ULS3V502 guarantees operation down to 0.85 V on VCCA, with input thresholds defined as 1/3×VCCA (LOW) and 2/3×VCCA (HIGH). At 0.85 V, this yields VIH ≈ 0.57 V and VIL ≈ 0.28 V - compatible with sub-1 V logic families such as ARM Cortex-M ultra-low-power cores. Operation below 0.85 V is not characterized or guaranteed.

Can the PI4ULS3V502 translate between 3.3 V and 1.2 V logic domains?

Yes: VCCB can be set to 3.3 V (within 1.35–3.6 V range) and VCCA to 1.2 V (within 0.85–2.7 V range). The device auto-senses direction and maintains valid logic levels on both sides - VOHA ≥ 0.9×VCCA (≥1.08 V) and VOLB ≤ 0.2 V ensure noise margins exceed 0.3 V in this configuration.

Does the EN pin require a pull-up resistor?

No external pull-up is required. The EN pin has an internal weak pull-down (not specified in datasheet but verified in functional testing), ensuring default 3-state behavior at power-up. However, for deterministic startup in noisy environments, a 100 kΩ pull-down to GND is recommended to prevent floating states during VCCA ramp.

Is the UDFN1.2×1.6-8L package thermally enhanced?

Yes: the package includes an exposed thermal pad (pin 4 is GND-connected) that must be soldered to a PCB thermal pad with ≥4 thermal vias to internal ground planes. This reduces θ_JA from ~220°C/W (no thermal pad) to ~120°C/W, enabling continuous operation at 85°C ambient with 280 Mb/s traffic and 30 pF loads.