Diodes Incorporated PI6ULS5V9617AUEX

Overview

PI6ULS5V9617AUEX from Diodes Incorporated is a 2-channel bidirectional I²C-bus/SMBus repeater IC with voltage-level translation between 0.6V–5.5V (Port A) and 2.2V–5.5V (Port B), supporting Fast-mode Plus (1 MHz), arbitration, clock stretching, and 540 pF bus capacitance per side at full speed. It isolates bus segments for mixed-voltage systems such as 0.9V microcontrollers interfacing with 3.3V sensors in industrial IoT edge nodes.

For engineers reviewing the PI6ULS5V9617AUEX datasheet, PI6ULS5V9617AUEX pinout, PI6ULS5V9617AUEX application, or PI6ULS5V9617AUEX equivalent, key selection criteria include dual-supply level-shifting capability, open-drain I/O tolerance up to 5.5V, EN pin referenced to VCC(B), propagation delays under 103 ns, and compatibility with PMBus and multi-master SMBus topologies.

Technical Context

The PI6ULS5V9617AUEX implements two independent bidirectional open-drain buffers with asymmetric voltage references: Port A uses dynamic thresholding (0.35×VCC(A)) for sub-1V logic compatibility, while Port B employs static offset buffering (0.55V VOL) to prevent lockup during low-voltage transitions. Its internal power-up sequencing ensures drivers remain disabled until VCC(B) ≥ 2.2V and internal references settle (~400 μs).

It supports star and daisy-chain topologies-multiple Port A buses can be connected in parallel, and series cascading (Port A → Port B) adds only time-of-flight delay without cumulative voltage offset. The EN pin, referenced to VCC(B), must transition only during bus idle states to avoid bus hang or protocol corruption.

Key Specifications

Pinout & Package

PI6ULS5V9617AUEX is packaged in an 8-pin MSOP (U) with 0.65 mm pitch, optimized for space-constrained industrial control and portable electronics. Thermal resistance θ_JA = 180°C/W supports operation up to +85°C ambient without forced airflow.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C-bus repeater applications.

Compared with TCA9617A and PCA9517A, PI6ULS5V9617AUEX uniquely supports 0.6V logic, 1 MHz operation, and star-topology expansion - making it the sole option for next-generation ultra-low-power, high-bandwidth I²C interconnects.

Availability

PI6ULS5V9617AUEX is available at Aetrix Electronics and suitable for industrial sensor hubs, automotive body controllers, medical wearables, and server BMCs requiring stable component supply across extended product lifecycles.

Supply support for PI6ULS5V9617AUEX 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 semiconductor company specializing in discrete, analog, and mixed-signal ICs for power management, signal integrity, and connectivity applications.

The PI6ULS5V9617A belongs to Diodes' Pericom® I²C/SMBus repeater family, engineered specifically for voltage-domain bridging in heterogeneous embedded systems where ultra-low-voltage logic coexists with legacy 3.3V/5V peripherals.

FAQ

Can PI6ULS5V9617AUEX operate with VCC(A) = 0.6V and VCC(B) = 2.2V simultaneously?

Yes. The device is fully specified down to 0.6V on Port A and 2.2V on Port B, with guaranteed functionality including 1 MHz operation, 540 pF bus loading, and proper LOW-level translation (VOL ≤ 0.2V on Port A). The 0.4×VCC(A) + 0.8V ≤ VCC(B) constraint is satisfied (0.4×0.6 + 0.8 = 1.04V ≤ 2.2V), ensuring channel enablement and stable comparator operation.

What happens to I²C signals when VCC(B) is unpowered but VCC(A) is active?

All I/O pins enter high-impedance state with leakage <±1 μA, preventing back-powering or signal corruption. Port A pins (SCLA/SDAA) remain 5.5V-tolerant and floating, while Port B pins (SCLB/SDAB) disconnect entirely. No current flows through internal drivers, and EN is inactive - the device behaves as an open circuit, preserving bus integrity in partial-power-down scenarios.

Is PI6ULS5V9617AUEX compatible with PMBus-compliant devices?

Yes. It transparently supports PMBus 1.1/1.2 signaling, including packet error checking (PEC), write-protect commands, and alert response protocols. Its open-drain I/O, arbitration preservation, and clock stretching transparency meet PMBus physical layer requirements. No configuration or external components are needed - it operates as a passive bus extender.

Why does the EN pin reference VCC(B) instead of VCC(A)?

Because all internal logic, drivers, and comparators are powered from VCC(B); referencing EN to VCC(B) ensures consistent threshold behavior regardless of VCC(A) level. This avoids undefined states during power sequencing and guarantees EN activation only when the core logic supply is valid - critical for reliable power-up isolation in mixed-rail systems.