NXP Semiconductors PCA9516APW,112

Overview

PCA9516APW,112 from NXP Semiconductors is a 5-channel bidirectional I²C-bus and SMBus repeater hub with open-drain I/O, active HIGH enable inputs (EN1–EN4), 2.3 V to 3.6 V supply operation, and 5.5 V tolerant bus/enable pins. It extends I²C-bus capacity to five 400 pF segments while preserving arbitration, clock stretching, and multi-master compatibility - deployed in mixed-voltage industrial sensor networks.

For engineers reviewing the PCA9516APW,112 datasheet, PCA9516APW,112 pinout, PCA9516APW,112 application, or PCA9516APW,112 equivalent, key selection criteria include per-channel enable control, VOL = 0.52 V typical output low voltage, 70 mV guaranteed VOL−VILc margin for contention detection, and TSSOP16 package compatibility with high-density PCB layouts.

Technical Context

The PCA9516APW,112 implements five independent bidirectional open-drain buffers with static offset-based lock-up prevention: input threshold (VILc) is set ~70 mV below output low voltage (VOL), ensuring reliable propagation of LOW signals across segments without latching. Each buffer pair handles SDA/SCL independently and supports Standard-mode (100 kHz) and Fast-mode (400 kHz) timing.

Enable logic uses internal pull-up resistors on EN1–EN4; channels disable both input sensing and output drive when asserted LOW, isolating bus segments during idle transitions. No direction pin is required, and series cascading is explicitly prohibited due to voltage-level incompatibility between buffered LOW outputs and subsequent repeater inputs.

Key Specifications

Pinout & Package

TSSOP16 package (SOT403-1): plastic thin shrink small outline, 16 leads, 4.4 mm body width, 0.65 mm lead pitch, surface-mount compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCA9516APW,112, the PCA9517APW,118 offers simpler point-to-point extension but no multi-segment flexibility, while the TCA9517PWR provides vendor diversity at the cost of slightly higher propagation delay and unverified contention margin in mixed-NXP systems.

Availability

PCA9516APW,112 is available at Aetrix Electronics and suitable for industrial sensor hubs, mixed-voltage system interconnects, multi-speed I²C isolation, and modular subsystem expansion requiring stable component supply and long-term lifecycle support.

Supply support for PCA9516APW,112 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The PCA9516A product line delivers scalable I²C-bus expansion for systems constrained by capacitance limits or voltage domain boundaries - designed specifically for robust multi-segment industrial communication without protocol degradation.

FAQ

What is the maximum I²C-bus clock frequency supported by the PCA9516APW,112?

The PCA9516APW,112 supports Fast-mode I²C-bus operation up to 400 kHz. However, actual system frequency may be lower due to cumulative propagation delays across repeater stages; design validation must confirm timing margins at the target clock rate using measured tPHL/tPLH values from the datasheet.

Can multiple PCA9516APW,112 devices be connected in series to extend beyond five segments?

No. The PCA9516APW,112 design explicitly prohibits series cascading: its buffered LOW output voltage (~0.52 V) falls outside the valid LOW input threshold (VILc ≤ 0.4 V) of another PCA9516APW,112, causing signal recognition failure. Only star-topology connections from a single hub are supported.

How does the PCA9516APW,112 handle voltage-level translation between 3.3 V and 5 V I²C buses?

The PCA9516APW,112 achieves voltage-level translation through 5.5 V tolerant I/O pins and open-drain architecture - no internal level-shifting circuitry is used. Pull-up resistors on each segment set local HIGH voltage (e.g., 3.3 V on SDA0, 5 V on SDA3), while the repeater passes LOW signals transparently across domains using its VOL specification.

What is the purpose of the VOL−VILc parameter in the PCA9516APW,112 datasheet?

The VOL−VILc parameter (guaranteed ≥70 mV) defines the minimum voltage margin between the PCA9516APW,112's output LOW level (VOL) and the input LOW threshold (VILc) for subsequent LOW assertions. This margin ensures reliable detection of contention events across segments and prevents metastability during arbitration.

Does the PCA9516APW,112 require external pull-up resistors on all bus segments?

Yes. Each SCLn and SDAn line - including SCL0/SDA0 and all five segments - requires dedicated external pull-up resistors. The PCA9516APW,112 contains no internal pull-ups; resistor values must be selected per segment load and speed (e.g., 2.2 kΩ for 400 kHz, 10 kΩ for 100 kHz) as specified in NXP application note AN255.