Diodes Incorporated PI6ULS5V9517AZEEX

Overview

PI6ULS5V9517AZEEX from Diodes Incorporated is a dual-channel, bidirectional I²C/SMBus repeater with independent voltage translation: Port A supports 0.8 V to 5.5 V, Port B supports 2.2 V to 5.5 V, and it enables bus extension up to 400 pF per segment while maintaining Standard- and Fast-mode (≤400 kHz) timing integrity. It features active-HIGH enable, open-drain I/Os, lock-up free operation, and 5.5 V-tolerant pins - deployed in mixed-voltage server management, industrial sensor hubs, and multi-rail embedded controllers.

For engineers reviewing the PI6ULS5V9517AZEEX datasheet, PI6ULS5V9517AZEEX pinout, PI6ULS5V9517AZEEX application, or PI6ULS5V9517AZEEX equivalent, key selection criteria include asymmetric supply rail support (0.8 V ↔ 2.2 V), propagation delay asymmetry (A→B: 25–110 ns; B→A: 15–300 ns), buffered low-level signaling on Port B (~0.5 V), and star/series topology compatibility for distributed I²C systems.

Technical Context

The device implements two independent bidirectional level-shifting channels using comparator-based edge detection and CMOS hysteresis inputs: Port A uses a 0.3×V_CC(A) input threshold to accommodate sub-1.0 V logic, while Port B employs a 0.7×V_CC(B) VIH and a contention-aware 0.4 V low-level recognition window to prevent bus lockup. Internal drivers are powered solely by V_CC(B), with V_CC(A) used only for reference generation and power-good sensing.

Propagation delays are load-dependent (1.35 kΩ/57 pF on Port B; 167 Ω/57 pF on Port A), and transition times vary with supply: t_THL on Port A ranges from 1 ns (V_CC(A) ≥ 3 V) to 105 ns (V_CC(A) ≤ 2.7 V). The EN pin must remain static during I²C transactions to avoid bus hang - state changes are only safe during full bus idle conditions.

Key Specifications

Pinout & Package

PI6ULS5V9517AZEEX is housed in an 8-pin TDFN package (2 mm × 3 mm, 0.5 mm pitch) with exposed thermal pad. Pin 1 is V_CC(A); pin 5 is EN; pins 2/3/6/7 carry SCL/SDA signals; pin 4 is GND; pin 8 is V_CC(B). The exposed pad must be soldered to a PCB thermal pad with vias for electrical stability and thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCA9515DP and TCA9517DGKR, PI6ULS5V9517AZEEX uniquely supports 0.8 V logic domains, provides hardware-enforced lock-up immunity via Port B's 0.4 V low-threshold, and delivers lower system-level power (500 μA ICC(A)) - making it optimal for battery-powered or heterogeneous-voltage embedded systems.

Availability

PI6ULS5V9517AZEEX is available at Aetrix Electronics and suitable for server baseboard management, industrial sensor hubs, and automotive body control modules requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for PI6ULS5V9517AZEEX 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, specializing in high-performance, energy-efficient solutions for power management, signal integrity, and connectivity applications.

The PI6ULS5V9517A belongs to Diodes' Pericom® interface product line, engineered specifically for robust, low-latency I²C/SMBus signal conditioning in mixed-voltage industrial, computing, and automotive systems.

FAQ

Can PI6ULS5V9517AZEEX operate with Port A at 0.8 V and Port B at 5.5 V simultaneously?

Yes. The device is explicitly rated for Port A supply from 0.8 V to 5.5 V and Port B from 2.2 V to 5.5 V. At 0.8 V on Port A, the input low threshold is 0.25×V_CC(A) = 0.2 V, ensuring reliable detection of weak low signals. All internal logic and drivers are powered by V_CC(B), so 5.5 V on Port B is fully supported without derating.

What happens if the EN pin is toggled during an active I²C transaction?

Toggling EN during a transaction will cause immediate bus hang. When disabled mid-cycle, the repeater stops propagating SDA/SCL edges, freezing the bus in an undefined state. The datasheet mandates EN state changes only during full bus idle (both SDA and SCL held HIGH for >100 ns before and after toggle) to guarantee protocol compliance and avoid system lockup.

Why does Port B have a ~0.5 V output low instead of near-0 V?

The ~0.5 V buffered low is intentional circuit design to prevent lock-up: it ensures Port B's low signal is not recognized as a valid low by its own input stage (which requires <0.4 V), avoiding self-latching. External pull-ups then lift the line to full HIGH. This enables reliable arbitration and clock stretching across voltage domains without software intervention.

Is the exposed thermal pad on the ZE package electrically connected?

Yes. The exposed pad on the TDFN-8 (ZE) package is internally connected to GND. It must be soldered to a PCB thermal pad tied to the system ground plane. Thermal vias beneath the pad are required for optimal electrical stability, heat dissipation, and mechanical reliability - omission risks increased junction temperature and intermittent I/O failures.