Texas Instruments TXE8124 I/O Expanders
Texas Instruments TXE8124 I/O Expanders provide general-purpose parallel input/output expansion for four-wire Serial Peripheral Interface (SPI) systems. The devices support point-to-point communication and daisy-chaining of multiple devices, helping add I/O to switches, sensors, push-buttons, LEDs, fans, and other processor designs with limited GPIO.
The TXE8124 includes three I/O ports with eight I/Os each, offering enhanced flexibility for speed, power consumption, and I/O configuration. The TI TXE8124 I/O Expanders support per-I/O input or output configuration, push-pull or open-drain output selection, pull-up or pull-down selection, bus-hold latchable inputs, maskable interrupts, status registers, glitch filtering, and fail-safe register mode.
These I/O expanders are ideal for industrial transportation, industrial automation, testing and measurement, factory automation and control, medical and healthcare, servers, routers, and products with GPIO-limited processors. The TXE8124 is available in 32-pin VSSOP and VQFN packages and supports operation over a -40°C to +125°C temperature range.
Features
- SPI I/O expansion for four-wire SPI protocol systems
- Standard point-to-point communication and daisy-chain support for multiple devices
- SPI read and write with burst mode
- Multi-port SPI command for configuring multiple ports simultaneously
- Active-low reset input and open-drain active-low interrupt output
- Interrupt mask, interrupt status per I/O, and interrupt status per port
- Built-in fail-safe I/O feature enabled by the FAIL-SAFE pin
- Individual I/O configuration options
- Input and output function selection
- Polarity inversion
- Push-pull and open-drain output selection
- Pull-up or pull-down selection
- Bus-hold feature to maintain the last I/O state
- Glitch filter enable selection
- Latched outputs with 10mA drive capability for directly driving LEDs
Applications
- Industrial transportation
- Industrial automation
- Testing and measurement
- Factory automation and control
- Medical and healthcare
- Servers
- Routers (telecom switching equipment)
- Products with GPIO-limited processors
Specifications
- 24 I/Os across three 8-bit ports
- Supply voltage range of 1.65V to 5.5V
- SPI SCLK frequency
- 10MHz from 3.3V to 5.5V
- 5MHz from 1.65V to 5.5V
- Low standby current consumption of 2.3µA typical
- IOFF support on input port pins
- Latch-up performance exceeding 100mA per JESD 78, class II
- ESD protection
- 2000V human-body model per JESD 22 A114-A
- 1000V charged-device model per JESD 22 C101
- Operating temperature range of -40°C to +125°C
- Package options
- 32-pin VSSOP package, 8mm x 5mm
- 32-pin VQFN package, 5mm x 5mm
Eval Module
Texas Instruments TXE81xxEVM Evaluation Module
Engineered for the evaluation of the TXE81xx family of SPI I/O expanders.
Simplified Schematic
Logic Diagram
