SDAA267 January   2026 TCA9539-Q1 , TCA9539A-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction to TCA9539A-Q1 I2C GPIO expander
  5. 2Key Specification Comparison: TCA9539A-Q1 vs TCA9539-Q1
    1. 2.1 I²C Addressing Scheme and Compatibility
    2. 2.2 Multidevice and Zonal Architectures
  6. 3Why Use Interrupts with I²C GPIO Expanders?
  7. 4Application Examples Using TCA9539A-Q1
    1. 4.1 Zonal Controller
    2. 4.2 Infotainment and ADAS Peripheral Control
    3. 4.3 Automotive Body Control Module (BCM)
    4. 4.4 Audio and Peripheral Monitoring
  8. 5Summary
  9. 6References

2 Key Specification Comparison: TCA9539A-Q1 vs TCA9539-Q1

The TCA9539AQPWRQ1 is designed to be pin-to-pin compatible with TCA9539-Q1 and TCA9539QPWRQ1, supporting direct replacement in existing designs without requiring schematic, layout, or firmware changes in applications detailed in Application Examples Using TCA9539A-Q1.

Table 2-2 lists key specifications relevant for migration from TCA9539-Q1 to TCA9539A-Q1.

Table 2-1 Comparison Table: TCA9539-Q1 and TCA9539A-Q1
Parameter TCA9539-Q1 TCA9539A-Q1
Supply Voltage Range 1.65V to 3.6V 1.65V to 5.5V
GPIO Count 16 16
I²C Data Rate Up to 400kHz (Fast-mode) Up to 400kHz (Fast-mode)
Operating Temperature –40°C to 125°C –40°C to 125°C
Maximum Junction Temp (TJ) 135°C 140°C
5V Tolerant I/Os Yes Yes
VOL / IOL
VOH / IOH		 0.5 V at 8mA, 0.7V at 10mA

3.3V at –8mA, 3.2V at –10mA

 0.5V at 8mA, 0.7 V at 10mA
4.7V at –8mA, 4.5 V at –10mA
Reset Pin Yes Yes
Interrupt Output Yes Yes
Number of I²C Addresses Four (TCA9539QPWRQ1) Eight
ESD (HBM) ±2kV ±2kV
ESD (CDM) ±1kV ±1kV
Package TSSOP-24 TSSOP-24