Remote 8-Bit I2C and Low-Power I/O Expander With Interrupt Output and Configuration Registers - PCA9534

PCA9534 (ACTIVE)

Remote 8-Bit I2C and Low-Power I/O Expander With Interrupt Output and Configuration Registers

 

Recommended alternative parts

  • TCA9534  - The device has the SAME FUNCTIONALITY and PINOUT as the compared device but is NOT an exact equivalent.   TCA9534 is an enhanced version of the PCA9534 with an extended supply voltage range and performance enhancements related to Power-On Reset.

Description

This 8-bit I/O expander for the two-line bidirectional bus (I2C) is designed for 2.3-V to 5.5-V VCC operation. It provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface [serial clock (SCL), serial data (SDA)].

The PCA9534 consists of one 8-bit Configuration (input or output selection), Input Port, Output Port, and Polarity Inversion (active high or active low) register. At power on, the I/Os are configured as inputs. However, the system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for each input or output is kept in the corresponding Input or Output register. The polarity of the Input Port register can be inverted with the Polarity Inversion register. All registers can be read by the system master.

The system master can reset the PCA9534 in the event of a timeout or other improper operation by utilizing the power-on reset feature, which puts the registers in their default state and initializes the I2C/SMBus state machine.

The PCA9534 open-drain interrupt (INT) output is activated when any input state differs from its corresponding input port register state and is used to indicate to the system master that an input state has changed.

INT can be connected to the interrupt input of a microcontroller. By sending an interrupt signal on this line, the remote I/O can inform the microcontroller if there is incoming data on its ports without having to communicate via the I2C bus. Thus, the PCA9534 can remain a simple slave device.

The device's outputs (latched) have high-current drive capability for directly driving LEDs. It has low current consumption.

Three hardware pins (A0, A1, and A2) are used to program and vary the fixed I2C address and allow up to eight devices to share the same I2C bus or SMBus.

The PCA9534 is pin-to-pin and I2C address compatible with the PCF8574. However, software changes are required due to the enhancements in the PCA9534 over the PCF8574.

The PCA9534 is a low-power version of the PCA9554. The only difference between the PCA9534 and PCA9554 is that the PCA9534 eliminates an internal I/O pullup resistor, which dramatically reduces power consumption in the standby mode when the I/Os are held low.

The PCA9534A and PCA9534 are identical, except for their fixed I2C address. This allows for up to 16 of these devices (8 of each) on the same I2C bus.

Features

  • Low Standby Current Consumption of 1 μA Max
  • I2C to Parallel Port Expander
  • Open-Drain Active-Low Interrupt Output
  • Operating Power-Supply Voltage Range of 2.3 V to 5.5 V
  • 5-V Tolerant I/O Ports
  • 400-kHz Fast I2C Bus
  • Three Hardware Address Pins Allow up to Eight Devices on the I2C/SMBus
  • Allows Up to 16 Devices on the I2C/SMBus When Used in Conjunction with the PCA9534A
    See for I2C Expander offerings
  • Input/Output Configuration Register
  • Polarity Inversion Register
  • Internal Power-On Reset
  • Power-Up With All Channels Configured as Inputs
  • No Glitch on Power Up
  • Noise Filter on SCL/SDA Inputs
  • Latched Outputs With High-Current Drive Maximum Capability for Directly Driving LEDs
  • Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 200-V Machine Model (A115-A)
    • 1000-V Charged-Device Model (C101)

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Parametrics Compare all products in I2C IO Expander

 
Pin/Package
Voltage Nodes (V)
Operating Temperature Range (C)
Max Frequency (kHz)
I2C Address
# of I/Os
Rating
Special Features
PCA9534 PCA9534A TCA7408 TCA9538 TCA9554
16SSOP
16TVSOP
16TSSOP
16VQFN
16SOIC   
16QFN
16SSOP
16SOIC
16TSSOP
16TVSOP
16VQFN   
16uCSP    16SSOP
16TSSOP   
16SOIC
16SSOP
16TSSOP   
2.7
3.3
3.6
5   
2.7
3.3
3.6
5   
1.8
2.7
3.3
3.6
5   
1.8
2.7
3.3
3.6
5   
1.8
2.7
3.3
3.6
5   
-40 to 85    -40 to 85    -40 to 85    -40 to 85    -40 to 85   
400    400    400    400    400   
0100 xxx    0111 xxx    0100 00x    1110 0xx    0100 xxx   
8    8    8    8    8   
Catalog    Catalog    Catalog    Catalog    Catalog   
5V Tolerant I/O
Configuration Registers
Interrupt Driven
Interrupt Output
Low Power
Push-Pull I/O Type   
5V Tolerant I/O
Configuration Registers
Interrupt Driven
Interrupt Output
Low Power
Push-Pull I/O Type   
Configuration Registers
Interrupt Driven
Interrupt Output
Low Power
Low Voltage
Programmable Pull-Up/Pull-Down
Push-Pull I/O Type
Reset Input   
Configuration Registers
Interrupt Output
Reset Input   
5V Tolerant I/O
Configuration Registers
Interrupt Driven
Interrupt Output
Low Power
Low Voltage
Push-Pull I/O Type   

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