Key Selection Information
| Selection Parameter | Confirmed Information |
|---|---|
| GPIO | 16 configurable I/O pins |
| Supply | Low-voltage family operation to 5.5 V |
| Bus | I²C/SMBus up to 400 kHz |
| Addressing | 2 address pins; up to 4 devices |
| Control | Active-low RESET and open-drain INT |
| Registers | Input/output/configuration/polarity inversion |
| Startup | Internal power-on reset; no-glitch startup |
| Exact Package / Packing | TSSOP (PW), 24 pins; 2000-piece large tape and reel |
Product Overview
TCA9539PWR provides 16 general GPIOs plus a dedicated active-low RESET input. That reset pin is the main system-level differentiator from 16-bit expanders such as TCA9555/PCA9555 that rely on power-on reset and software state.
Two address pins allow four devices on one I²C segment. This is fewer than the eight address choices of TCA9555, so a design with many 16-bit expanders may prefer address flexibility over hardware reset.
The PWR exact order code is the TSSOP-24 large-reel version, retaining visible leads for manufacturing and debug.
For related devices, see HKEQGOO’s I/O Expanders category.
Technical Specifications
| Parameter | Verified Information |
|---|---|
| Manufacturer | Texas Instruments |
| Exact MPN | TCA9539PWR |
| GPIO | 16 configurable I/O pins |
| Supply | Low-voltage family operation to 5.5 V |
| Bus | I²C/SMBus up to 400 kHz |
| Addressing | 2 address pins; up to 4 devices |
| Control | Active-low RESET and open-drain INT |
| Registers | Input/output/configuration/polarity inversion |
| Startup | Internal power-on reset; no-glitch startup |
| Exact Package / Packing | TSSOP (PW), 24 pins; 2000-piece large tape and reel |
| Manufacturer Status | Active / Production |
| Part Marking | PW539 |
Functional Highlights
Hardware RESET supports deterministic fault recovery
A supervisor or host GPIO can force all ports back to their default input state without cycling the shared supply, useful when external peripherals must be released after a software/bus fault.
Reset capability trades against address density
TCA9539 uses two address pins. If more than four devices are required on one bus, muxing or a different expander family may be simpler.
Design Considerations
- Connect RESET to a defined level and include it in boot/fault sequencing; do not leave recovery behavior accidental.
- Plan I²C address allocation before committing to multiple TCA9539 nodes.
- Initialize desired output values before enabling pins as outputs after reset.
Product Status and Exact Order Code
Manufacturer status: Active / Production
Texas Instruments lists TCA9539PWR as Active / Production; TSSOP (PW), 24 pins; 2000-piece large tape and reel; Level-1-260C-UNLIM; −40°C to +85°C; marking PW539.
Related Engineering Resources
Quality & Verification Support
Third-party inspection or testing can be arranged according to customer requirements. Testing fees are borne by the buyer. Additional verification requirements can be discussed before shipment. After an order is placed, physical product, label, packaging, and Date Code photos may be provided where appropriate.
Request a Quote
To request a quotation, provide the manufacturer part number, required quantity, destination, target Date Code if applicable, and any testing or inspection requirements.
