PCA9535DBR - 16-Bit I2C I/O Expander | Texas Instruments
料号： PCA9535DBR ✗ 停产PCA9535DBR 概述
An I/O expander is an interface IC that translates serial commands into parallel digital input or output operations. The PCA9535DBR belongs to the I/O expander hierarchy within interface controllers and system interface ICs. Its remote port architecture allows a controller to monitor inputs and control outputs located behind cables, bus isolators, or other serial links, reducing the number of host GPIO pins required on compact industrial, embedded, and communications equipment.
The device operates from 2.3 V to 5.5 V and supports I2C and SMBus communication at up to 400 kHz. Sixteen I/O pins can be configured individually as inputs or outputs through configuration registers. An interrupt output provides a change-event indication, while the configuration registers retain port settings. The verified distributor information also identifies a maximum standby current of 1 uA, helping reduce power consumption when the system is inactive.
Internally, the PCA9535 consists of two 8-bit I/O port groups connected to the serial interface. Each port provides eight configurable lines, creating a total of 16 I/O resources. The pin-to-pin and I2C address compatibility stated by Texas Instruments relative to the PCF8575 does not mean that existing firmware is always portable, because the enhanced register behavior requires software changes. This distinction is important when planning a replacement or driver migration.
Typical uses include remote control panels, industrial automation modules, sensor and relay interfaces, embedded control boards, and communications equipment. The device is particularly useful when a system needs more GPIO lines than the host controller provides or when the controlled signals are physically remote from the processor. The 24-pin SSOP package also makes it practical for compact boards requiring a conventional leaded surface-mount footprint.
When designing a circuit, account for the I2C pull-up resistors, bus capacitance, address selection, and the electrical requirements of every attached port. Check that connected loads remain within the device's output-current and absolute-maximum ratings. Although the PCA9535DBR and its alternatives may use related interfaces, firmware must be checked for register-map differences, input polarity, and interrupt behavior before substitution.
This product record combines the verified manufacturer and distributor details with package, purchasing, replacement, and application guidance. It is intended to support faster part identification while clearly separating confirmed PCA9535DBR specifications from parameters that still require confirmation from the manufacturer datasheet.
直接替换替代料： PCA9535DBR ——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： PCA9535DBR （相同外形与封装尺寸） ——差异在于 Package, Interface, Interrupt Output, Packaging, Device Type.
TCA9535DBR
✅ 直接替换📋 参考替代料（不在目录中）
TCA9555DBR
✅ 直接替换📋 参考替代料（不在目录中）
PCA9535DB
✅ 直接替换联系询价
查看数据手册 →PCA9535DBQ
✅ 直接替换📋 参考替代料（不在目录中）
PCAL9535A
✅ 直接替换📋 参考替代料（不在目录中）
PCA9535DBR 规格参数
| Number of I/O Lines | 16 lines |
| 接口 | I2C and SMBus |
| Supply Voltage Range | 2.3 V to 5.5 V |
| Maximum Bus Clock Frequency | 400 kHz |
| Interrupt Output | Yes |
| Configuration Registers | Yes |
| Maximum Standby Current | 1 uA |
| 封装 | 24-SSOP (0.209 inch, 5.30 mm width) |
| 安装类型 | Surface mount |
| Packaging | Cut Tape |
| I/O Port Organization | Two 8-bit ports, 16 I/O total |
| Low-Power Operation | Low standby-current operation |
| Host GPIO Reduction | 16 host I/O lines |
PCA9535DBR 24-ssop (0.209 inch, 5.30 mm width) 引脚配置指南
PCA9535DBR（24-ssop (0.209 inch, 5.30 mm width) 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： PCA9535DBR.
请参阅 数据手册 以查看完整引脚配置。
典型应用
PCA9535DBR 适用于 6 应用s: Industrial Automation Remote I/O, Server and Communications Control Panels, Sensor and Relay Interface Module, Remote Operator Panel, Embedded Data Acquisition System, Low-Power Sensor Hub.
Industrial Automation Remote I/O
The PCA9535DBR fits remote I/O modules because it adds 16 configurable digital lines over a 400 kHz I2C connection while operating from 2.3 V to 5.5 V. A controller can use the expander for pushbuttons, discrete sensor inputs, relay-control outputs, and panel status indicators without consuming 16 host GPIO pins. The interrupt output can signal a port change and reduce unnecessary polling. Confirm the output-current limits, industrial temperature range, and transient-protection requirements from the manufacturer datasheet before deployment.
推荐
Server and Communications Control Panels
PCA9535DBR is useful in communications and server-adjacent control panels where front-panel indicators, configuration switches, and status inputs require more parallel lines than the host processor can expose directly. Its 16-bit remote port, 2.3 V to 5.5 V supply range, and 400 kHz I2C mode provide a compact interface between the controller and panel circuitry. The interrupt function can alert the host to relevant input changes. Verify timing margin at the maximum bus rate and confirm the current limits for LED or logic loads.
推荐
Sensor and Relay Interface Module
The PCA9535DBR can bridge a microcontroller to external sensors, optocouplers, latches, and relay drivers when direct host GPIO capacity is limited. Each of the 16 lines can be assigned as an input or output through configuration registers, allowing one serial bus to handle both acquisition and command paths. With a 400 kHz interface and 2.3 V to 5.5 V operating range, it supports mixed embedded systems, but output drive current, inductive-load protection, and isolation must be designed around the exact electrical limits.
推荐
Remote Operator Panel
PCA9535DBR is well suited to a remote operator panel containing multiple pushbuttons, LEDs, selectors, and status lamps. The main controller configures the 16 ports over I2C, reads input states, and updates output indicators without requiring a dedicated GPIO header to each panel. Because the device supports 400 kHz operation and has a verified maximum standby current of 1 uA, it can also support power-conscious panels. Interface details such as debouncing, LED current, input polarity, and interrupt masking still need application-specific validation.
推荐
Embedded Data Acquisition System
The PCA9535DBR provides a simple way to collect discrete signals from a distributed acquisition board. Sixteen configurable inputs can represent alarms, threshold flags, module-presence signals, or sampled status lines, while the interrupt output identifies activity for the embedded controller. Its 2.3 V to 5.5 V supply range permits integration with both low-voltage and conventional 5 V logic when levels are compatible. Confirm the input voltage and leakage limits, then add suitable protection where field wiring exposes the board to transients.
推荐
Low-Power Sensor Hub
PCA9535DBR can extend a low-power sensor hub with configurable digital channels while preserving a compact serial footprint. Its verified 1 uA maximum standby current is useful when the hub spends most of its time idle, and the interrupt output permits wake-oriented control instead of continuous polling. The 2.3 V minimum operating voltage also supports low-voltage system rails. Use the configuration registers to minimize active current, confirm wake and reset behavior in the datasheet, and ensure attached sensors do not exceed the port drive limits.
推荐
推荐产品汇总
工程参考数据： PCA9535DBR ——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 | TCA9535DBR | TCA9555DBR | PCA9535DB | PCA9535DBQ | PCAL9535A |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | NXP Semiconductors |
| Package | 24-SSOP | 24-SSOP | 24-SSOP | 24-SSOP | 24-SSOP | 24-SSOP |
| Number of I/O Lines | 16 lines | 16 lines | 16 lines | 16 lines | 16 lines | 16 lines |
| Interface | I2C and SMBus | I2C | I2C | I2C and SMBus | I2C and SMBus | I2C |
关键差异点
- Low standby consumption （对比 PCA9555 family)
- Wide confirmed operating range （对比 PCAL9535A)
- Established Texas Instruments compatibility path （对比 PCA9535DB)
设计说明
Do not treat package equivalence as proof that firmware is interchangeable. Texas Instruments states that the PCA9535 is pin-to-pin and I2C-address compatible with the PCF8575 but requires software changes because of enhancements. For every substitute, compare port configuration registers, input and output polarity, interrupt masking, reset values, addressing, and timing before releasing replacement firmware.
Use the confirmed 2.3 V to 5.5 V operating range to select the regulator and level-shift strategy for the PCA9535DBR. The verified maximum standby current is 1 uA, but total system power also depends on active current, pull-ups, and attached loads. Check the manufacturer limits for output drive and source current before using a port directly with LEDs, relays, or other non-light-load devices.
Place the I2C pull-up resistors at the physical end of the bus that requires the strongest pull-up, accounting for the bus length and capacitance. Keep the PCA9535DBR close to its intended connector or remote I/O circuitry when cable length is significant, and provide local return paths that reduce susceptibility to noise. The 400 kHz maximum bus rate must be validated against the complete wiring and peripheral load.
合规信息
The supplied verified excerpts do not state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status. AEC-Q100 is marked not applicable because no automotive qualification is identified for PCA9535DBR.
