TCA9535DBR - 16-Bit I2C I/O Expander | Texas Instruments
部品番号: TCA9535DBR ✓ 生産中TCA9535DBR 概要
An I/O expander is an interface IC that increases the number of digital input and output pins available to a host controller. The host communicates with the TCA9535DBR through a two-wire I2C or SMBus interface, while the 16 external lines handle logic inputs, outputs, or mixed functions. In the system hierarchy, this device belongs to the interface IC family and bridges a serial control bus with parallel digital signals.
The principal features are 16 independently configurable I/O pins, a 1.65 V to 5.5 V operating range, and a maximum bus frequency of 400 kHz. The interrupt output allows a connected controller to react when an input changes, reducing the need for continuous polling. Separate configuration registers support control of the direction and behavior of the I/O ports, while the device is designed for low-power operation.
TCA9535DBR is packaged in a 24-pin SSOP, providing a compact surface-mount format for programmable control, monitoring, and signal-routing boards. Its I2C interface is suitable for buses that also carry configuration data or communicate with sensors, memory, and other interface devices. The 400 kHz capability allows the expander to operate on standard low-speed I2C systems without changing the host protocol.
Typical applications include industrial control panels, programmable logic controllers, building automation equipment, test systems, and embedded products that require additional digital lines. The part can also expand button or switch inputs, control discrete logic signals, and provide interrupt-driven status reporting. Its small pin count relative to the number of external I/O lines helps conserve connector space and simplify system architecture.
When designing around the TCA9535DBR, account for address selection, pull-up requirements, input thresholds, and the electrical characteristics of every attached signal. Confirm the board footprint and pin assignment against the manufacturer datasheet before release, especially when replacing a device with similar I/O count but different input or output polarity. The design notes and comparisons on this page provide practical guidance for firmware setup, PCB layout, and device selection.
ドロップイン代替品: TCA9535DBR — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: TCA9535DBR （同一形状・フットプリント）.
PCA9535DBG4
✅ ドロップイン📋 参考代替品（カタログ未掲載）
TCA9535DBR 仕様
| Product Type | 16-bit I2C and SMBus I/O expander |
| Number of I/O Lines | 16 lines |
| Operating Voltage Range | 1.65 V to 5.5 V |
| Maximum I2C Bus Frequency | 400 kHz |
| Supported Serial Protocols | I2C and SMBus |
| インターフェースタイプ | Two-wire bidirectional serial interface |
| Interrupt Output | Yes |
| Configuration Registers | Yes |
| Package Type | 24-pin SSOP |
| Package Pin Count | 24 pins |
| 実装タイプ | Surface mount |
| Device Function | General-purpose parallel I/O expansion |
| Power Classification | Low-power I/O expander |
| Output Port Count | 2 ports of 8 lines |
| Input Port Count | 2 ports of 8 lines |
| Manufacturer Document Revision | Rev. F |
TCA9535DBR 24 pins ピン配置ガイド
TCA9535DBR (24 pins パッケージ) のピン配置。 ピン番号、機能、接続図はメーカーのデータシートで定義されています。正確なフットプリントとはんだ付けのガイドラインについては、データシートを参照してください。
詳細なピン配置データはありません: TCA9535DBR.
詳細は データシート をご参照ください。
主な用途
TCA9535DBR の用途: 6 件s: Industrial Control Panels, Programmable Logic Controller I/O, Building Automation Equipment, Embedded System Button and Indicator Expansion, Test and Measurement Equipment, Battery-Powered Portable Instrument.
Industrial Control Panels
The TCA9535DBR is useful in an industrial control panel that must monitor switches, selectors, and interlocks while driving indicator or actuator-control signals. Its 16 general-purpose I/O lines reduce pressure on a host controller’s limited pin count, and the 1.65 V to 5.5 V operating range supports low-voltage logic systems. The interrupt output can notify the controller of input changes, while the 400 kHz I2C limit provides a practical communication path for static panel signals. Verify signal levels, operating temperature, and isolation requirements in the final equipment design.
おすすめ
Programmable Logic Controller I/O
A programmable logic controller can use the TCA9535DBR when its base controller does not expose enough local input and output lines. Sixteen parallel lines can be configured for discrete field signals, while the device communicates over I2C or SMBus at up to 400 kHz. The interrupt output supports event-oriented handling of input changes, reducing unnecessary register polling. Firmware should initialize the configuration registers explicitly and validate the external signal levels, grounding, and noise margins for the particular controller installation.
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Building Automation Equipment
The TCA9535DBR can extend a building-automation controller for access switches, occupancy interfaces, alarm inputs, and discrete control signals. Its 16-bit parallel I/O structure reduces the number of host pins and wiring connections, while the 1.65 V to 5.5 V range provides compatibility with low-voltage control logic. The interrupt output helps the controller respond to changed field conditions, and the 400 kHz I2C interface can share a bus with other compatible peripherals. Confirm the deployment’s environmental and communication requirements before releasing the circuit.
おすすめ
Embedded System Button and Indicator Expansion
In an embedded product, the TCA9535DBR can connect more buttons, LEDs, mode selectors, or status indicators than the host controller can support directly. The 16 I/O lines are organized into two 8-line ports, allowing input and output functions to be combined, while configuration registers control the port behavior. The interrupt output provides a practical way to report button or status changes. Firmware must define stable pin roles, debounce external inputs as required, and account for the device’s 400 kHz maximum bus speed.
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Test and Measurement Equipment
The TCA9535DBR can expand the control interface of a test fixture or programmable measurement system that needs many low-speed digital connections. Sixteen I/O lines can control fixture relays, route status indicators, or collect interlock and configuration signals. The compact 24-pin SSOP package helps preserve board area, and the interrupt output can report fixture-state changes to the controller. Because the supported serial rate is 400 kHz, the device is best suited to static or low-update-rate signals rather than continuous high-speed sampling.
おすすめ
Battery-Powered Portable Instrument
A portable instrument can use the TCA9535DBR to add controls or status inputs without committing many microcontroller pins to a user interface. The device’s low-power design, 1.65 V to 5.5 V operating range, and 24-pin SSOP package support compact low-voltage designs. The I2C interface operates up to 400 kHz, which is suitable for slow control traffic, while the interrupt output avoids constant register reads when the user interface is idle. Power-budget calculations should include the expander, pull-ups, and any attached LED or switch circuitry.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: TCA9535DBR — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | PCA9535DBG4 |
|---|---|---|
| Brand | Texas Instruments | NXP Semiconductors |
| Package | 24-pin SSOP | 24-pin SSOP |
| I/O Lines | 16 lines | 16 lines |
| Serial Protocols | I2C and SMBus | I2C |
| Device Description | Remote 16-bit I2C and SMBus low-power I/O expander with interrupt output and configuration registers | 16-bit I2C I/O expander |
主な差別化要因
- Documents both I2C and SMBus operation （vs PCA9535DBG4)
- Provides a documented interrupt output and configuration registers （vs PCA9535DBG4)
- Supports a 5 V operating ceiling within a 1.65 V minimum （vs PCA9535DBG4)
設計ノート
Place the TCA9535DBR close to the supported connector or signal source and route the I2C clock and data lines as a compact, continuous pair. Provide the pull-up network required by the system’s bus voltage and topology, and keep the 24-pin SSOP footprint aligned with the manufacturer land pattern. Verify pin 1 orientation during assembly because an incorrect rotation can connect power, ground, address, and I/O lines to unintended circuit nodes.
Do not assume that two 16-bit I/O expanders are interchangeable because their I/O counts and packages match. Before replacing TCA9535DBR with PCA9535DBG4, compare numbered pin assignments, address-selection behavior, configuration registers, input and output polarity, and interrupt behavior. Existing firmware may also depend on register addresses or bit definitions, so validate the complete initialization and read/write sequence on hardware before production use.
Keep the I2C routing away from noisy switching nodes and high-slew-rate digital signals where practical. Stubs should be short, and pull-up placement should follow the physical topology of the bus rather than an arbitrary component position. Decoupling placement and grounding should follow the manufacturer’s recommended layout, with care taken not to interrupt current return paths or introduce long high-frequency return loops around the 24-pin SSOP.
Budget the TCA9535DBR, I2C pull-up current, and attached external loads together when evaluating a low-voltage supply. The supported 1.65 V to 5.5 V operating range does not guarantee identical logic-level behavior for every external signal. Confirm input thresholds, output levels, leakage current, and pull-up voltage against the host controller and attached circuitry. For portable systems, include the expander and bus termination in the standby-power calculation.
コンプライアンス情報
The available manufacturer and distributor information identifies the part and its Rev. F data sheet but does not provide extractable compliance declarations. RoHS, REACH, lead-free, halogen-free, and conflict-minerals status therefore remain unknown.