TCA9539PWR - 16-Bit I2C I/O Expander | Texas Instruments
料号： TCA9539PWR ✓ 量产中TCA9539PWR 概述
An I/O expander is an interface IC that extends the number of digital input or output pins available to a host processor. In the signal-chain hierarchy, it belongs to the I2C interface-controller family, connects to the broader interface-IC and semiconductor categories, and sits between embedded control systems and external sensors, switches, indicators, or logic inputs. The TCA9539 supports input, output, and mixed-direction operation for the 16 port lines.
The TCA9539 provides hardware-selectable A0 and A1 address inputs, allowing up to four devices to coexist on one I2C bus. Its interrupt output indicates when an input port changes state, allowing the host to avoid continuous polling. The reset and configuration registers provide defined startup and operating behavior, while power-on reset restores the default device state. Low-voltage operation supports systems built around modern embedded processors.
The device uses the I2C or SMBus two-wire protocol for communication. The TCA9539PWR is specified for 16 I/O channels, 400 kHz maximum clock frequency, and a 1.65 V to 5.5 V operating supply range. Its 24-TSSOP package is designed for surface-mount PCB assembly and provides a practical alternative to adding a second microcontroller or using a larger host package.
Typical applications include industrial control panels, sensor aggregation boards, LED and relay interfaces, battery-powered embedded systems, configurable GPIO modules, and compact consumer or communications equipment. The interrupt output is especially useful when multiple external inputs must be monitored while conserving host-processing time.
When laying out the circuit, place the device close to the associated connector or peripheral circuits and route the I2C lines away from high-current switching paths. Confirm pull-up resistor values against the bus voltage and capacitance. Use the manufacturer pin-description table when assigning PCB tracks and verify the device address, port direction, and reset state in firmware.
This page combines manufacturer specifications, compatible replacement guidance, comparison parameters, and practical design notes for engineers evaluating the TCA9539PWR in embedded I/O designs.
直接替换替代料： TCA9539PWR ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： TCA9539PWR （相同外形与封装尺寸） ——差异在于 Package, Supply Voltage Range, Interface, Product Type, Interrupt Output.
TCA9539QPWRQ1
✅ 直接替换📋 参考替代料（不在目录中）
TCA9539RTWR
✅ 直接替换📋 参考替代料（不在目录中）
PCA9539PWR
✅ 直接替换联系询价
查看数据手册 →TCA9535PWR
✅ 直接替换联系询价
查看数据手册 →PCA9555PWR
✅ 直接替换联系询价
查看数据手册 →TCA9539PWR 规格参数
| Product Type | 16-bit I2C and SMBus low-power I/O expander |
| Number of I/O Lines | 16 |
| Operating Supply Voltage Range | 1.65 V to 5.5 V |
| Maximum I2C Clock Frequency | 400 kHz |
| Serial Interface | I2C and SMBus |
| 封装 | 24-pin TSSOP (PW) |
| 安装类型 | Surface mount |
| Address Inputs | A0 and A1 hardware-selectable inputs |
| Maximum Devices per I2C Bus | 4 |
| Interrupt Output | Yes |
| Reset Input | Yes |
| Configuration Registers | Yes |
| Power-On Reset | Yes |
| Port Operation | Input, output, or mixed-direction operation |
| Number of Supply Pins | 2 |
TCA9539PWR 24-pin tssop (pw) 引脚配置指南
TCA9539PWR（24-pin tssop (pw) 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： TCA9539PWR.
请参阅 数据手册 以查看完整引脚配置。
典型应用
TCA9539PWR 适用于 6 应用s: Industrial Control Panel Interface, Sensor Aggregation Module, LED and Relay Control, Low-Voltage Embedded System, Communications Equipment, Battery-Powered Controller.
Industrial Control Panel Interface
The TCA9539PWR is a practical choice for industrial control panels requiring more digital lines than the host controller can provide directly. Its 16 I/O ports can operate as inputs for limit switches, interlocks, and panel status signals, or as outputs for indicator and actuator control. The 1.65 V to 5.5 V operating range supports common control-rail voltages, while the interrupt output lets the processor respond to changing input states without continuous polling. Use the A0 and A1 pins to assign distinct bus addresses when several panels or expansion groups share one I2C bus.
推荐
Sensor Aggregation Module
TCA9539PWR fits sensor-aggregation boards where multiple digital sensors, switches, or discrete status lines must be connected to a compact host processor. The 16 ports support input, output, or mixed configurations, allowing one serial bus to handle both sensed events and control signals. Its interrupt output improves responsiveness by signaling a changed input instead of requiring constant polling at 400 kHz bus speed. The wide 1.65 V to 5.5 V supply range is useful when sensors operate from different low-voltage rails, although each attached circuit must share a compatible logic reference.
推荐
LED and Relay Control
The TCA9539PWR can provide a compact control interface for LEDs, relay drivers, latches, and other discrete actuators that would otherwise consume many host GPIO pins. Sixteen configurable outputs free the processor for application logic and simplify the connector layout. Because the device is a digital I/O expander rather than a power driver, each output must remain within its specified current and voltage limits, and suitable transistor or driver stages are needed for relays and high-current loads. The interrupt input capability also allows selected status lines to be monitored alongside outputs.
推荐
Low-Voltage Embedded System
TCA9539PWR is suited to low-voltage embedded platforms where adding a larger host package solely for GPIO expansion would be inefficient. Operation from 1.65 V to 5.5 V supports processors operating around 1.8 V, 2.5 V, or 3.3 V, while the I2C interface reduces the number of physical connections. Mixed input/output operation supports compact keyboard, display, communication, and peripheral-control designs. Firmware should configure each port direction explicitly and use the interrupt mask registers to prevent unnecessary wakeups.
推荐
Communications Equipment
The TCA9539PWR can extend a communications module with front-panel indicators, equipment-enable signals, alarm inputs, and configuration switches. Its I2C/SMBus connectivity allows the communications controller to manage up to 16 lines while sharing the bus with other peripherals. A maximum bus clock of 400 kHz provides sufficient bandwidth for status updates, and the interrupt output supports prompt alarm handling. The TSSOP-24 footprint keeps the expansion compact, but board layout must preserve I2C signal integrity by minimizing trace length and keeping the bus away from noisy power-conversion paths.
推荐
Battery-Powered Controller
TCA9539PWR is useful in battery-powered controllers that need flexible digital I/O without adding a dedicated microcontroller or large GPIO package. Its low-voltage operation from 1.65 V to 5.5 V and interrupt mechanism can reduce unnecessary bus activity by allowing the host to sleep until an input event occurs. Sixteen ports can support wake sources, status LEDs, mode controls, and low-current peripherals. Firmware should disable unused ports and configure the interrupt mask to prevent false wakeups, while the power design must honor the device's specified operating range and supply requirements.
推荐
推荐产品汇总
工程参考数据： TCA9539PWR ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | TCA9539QPWRQ1 | TCA9539RTWR | PCA9539PWR | TCA9535PWR | PCA9555PWR |
|---|---|---|---|---|---|---|
| Package | TSSOP-24 (PW) | TSSOP-24 (PW) | TSSOP-24 (PW) | TSSOP-24 (PW) | TSSOP-24 (PW) | TSSOP-24 (PW) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Number of I/O Lines | 16 | 16 | 16 | 16 | 16 | 16 |
| Serial Interface | I2C and SMBus | I2C and SMBus | I2C and SMBus | I2C | I2C | I2C |
| Interrupt Output | Yes | Yes | Yes | Yes | Yes | Yes |
| Hardware Address Inputs | A0 and A1 | A0 and A1 | A0 and A1 | A0 and A1 | A0, A1, and A2 | A0, A1, and A2 |
| Reset and Configuration Registers | Yes | Yes | Yes | Yes | Yes | Yes |
关键差异点
- Direct same-family automotive qualification path （对比 TCA9539PWR)
- Native 1.65 V to 5.5 V operating range （对比 PCA9539PWR)
- Two address pins support four devices per bus （对比 PCA9555PWR)
设计说明
Place the TCA9539PWR near the connector or peripheral pins it serves to minimize trace length on the 16 I/O nets. Keep the I2C SCL and SDA routes short, route them away from switching-regulator inductors and high-current relay paths, and provide a continuous ground reference. Use the manufacturer's 24-pin TSSOP footprint and pin-description table to verify pad locations before fabrication.
Decouple VCC locally with the capacitance recommended by the manufacturer datasheet and place the capacitor close to the supply pins. Ensure the regulator can supply the device across the complete 1.65 V to 5.5 V operating range and that the I2C pull-up voltage is appropriate for the bus. Do not exceed the electrical limits listed for any output port, especially when driving external circuitry.
Calculate I2C pull-up resistance from the bus voltage, total bus capacitance, and required rise time. Confirm that the resulting pull-up current remains within the device and controller limits at the lowest operating voltage. Keep the bus topology short and avoid unnecessary stubs; if long cables or multiple branches are unavoidable, use an appropriate bus buffer or redesigned distribution.
Configure every port direction and output latch value before enabling the corresponding interrupt path. Incorrect startup port states can create unintended output transitions, so use the reset and power-on-reset behavior deliberately. When substituting another 16-bit expander, verify the register map, slave address, A0/A1 behavior, reset polarity, and interrupt-clearing procedure even when the package is identical.
合规信息
The standard TCA9539PWR is not identified as an automotive-qualified ordering option. RoHS, REACH, lead-free, halogen-free, and conflict-minerals status require confirmation from the manufacturer product documentation or declaration.