NXP Semiconductors PCA9701PW,112

Overview

PCA9701PW,112 from NXP Semiconductors is a 16-bit SPI General Purpose Input (GPI) shift register with open-drain interrupt output, designed for automotive switch monitoring. It features 18 V tolerant inputs (with ≥100 kΩ series resistor), 2.5–5.5 V supply range, 2.5 µA max IDD, and operates from −40 °C to +125 °C. Used in body control modules to monitor up to 16 mechanical or solid-state switches under harsh battery conditions.

For engineers reviewing the PCA9701PW,112 datasheet, PCA9701PW,112 pinout, PCA9701PW,112 application, or PCA9701PW,112 equivalent, key selection criteria include 18 V input tolerance with external resistor, SPI interface timing at up to 5 MHz, interrupt masking capability via INT_EN, low quiescent current for ECU standby, and TSSOP24 package compatibility with automotive PCB layouts.

Technical Context

The PCA9701PW,112 implements a 16-bit parallel-input/serial-output shift register synchronized to SPI clock edges: CS falling edge captures input port status into the input status register and clears interrupt; first SCLK rising edge loads the shift register; subsequent rising edges shift data out via SDOUT. Input sampling occurs on the falling edge of SCLK, with SDIN featuring a 20 µA internal pull-down.

Its GPI architecture supports cyclic biasing for SBC wake-up extension, enabling ultra-low system current (e.g., 50 µA in sleep mode with UJA106x). The open-drain INT output supports wired-AND connection across multiple devices, while INT_EN allows selective interrupt disabling without affecting input sampling or SPI communication.

Key Specifications

Pinout & Package

TSSOP24 package (SOT355-1): plastic thin shrink small outline, 24 leads, 4.4 mm body width, 0.65 mm pitch, lead-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar general-purpose input monitoring applications.

Compared with PCA9701PW,112, PCA9701HF,118 offers superior thermal dissipation in compact designs, while PCA9703PW,118 delivers tighter input threshold control and higher noise margin - both retain identical SPI protocol, interrupt behavior, and automotive qualification.

Availability

PCA9701PW,112 is available at Aetrix Electronics and suitable for body control modules, industrial emergency lighting controllers, and SBC wake pin extension applications requiring stable component supply across automotive production lifecycles.

Supply support for PCA9701PW,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 leader focused on automotive, industrial, IoT, and communication infrastructure solutions, with deep expertise in automotive electronics and functional safety.

The PCA9701PW,112 belongs to NXP's automotive-grade GPI portfolio, engineered specifically for robust switch monitoring in harsh environments - supporting ISO 16750-2, AEC-Q100 Grade 1, and CAN/LIN-based ECU architectures.

FAQ

What is the maximum input voltage the PCA9701PW,112 can tolerate on its IN0–IN15 pins?

The PCA9701PW,112 supports up to 18 V on its GPI inputs when used with a minimum 100 kΩ external series resistor. This enables safe operation during automotive transients including 40 V load dump events. Without the resistor, absolute maximum input voltage is 6 V per the datasheet limiting values table.

Does the PCA9701PW,112 require external pull-up resistors on its SDOUT and INT pins?

Yes - SDOUT is 3-state and requires an external pull-up (typically 4.7–10 kΩ) for proper SPI communication, especially in daisy-chained configurations. INT is open-drain and also requires a pull-up (recommended 10 kΩ) to generate a valid active-LOW signal for the host controller.

How does the INT_EN pin affect interrupt behavior in the PCA9701PW,112?

When INT_EN is driven LOW, the PCA9701PW,112 disables its interrupt output and places the INT pin in high-impedance state - no current flows and no voltage is driven. When INT_EN is HIGH, interrupt assertion follows normal behavior: active LOW on input state change, cleared by CS falling edge.

Can multiple PCA9701PW,112 devices share a single SPI bus and interrupt line?

Yes - multiple PCA9701PW,112 units can be daisy-chained via SDOUT-to-SDIN connections with shared CS, SCLK, and SDIN lines. Their open-drain INT outputs may be tied together with one pull-up resistor, forming a wired-AND bus that asserts if any device detects a switch change.

What is the minimum series resistor required for connecting the PCA9701PW,112 to a 27 V jump-start source?

A minimum 100 kΩ series resistor is required for all GPI inputs when applied voltage exceeds 5.5 V. For 27 V jump-start conditions, this resistor limits input current to ≤100 µA (per Table 6), preventing latch-up and ensuring ESD protection circuit integrity - lower resistance risks permanent damage and voids warranty.