PCA9554DW

Product Overview

Category: Integrated Circuit (IC)

Use: The PCA9554DW is a 16-bit I2C-bus and SMBus I/O expander optimized for dimming LEDs in applications such as backlight control, keypad illumination, and other similar lighting control functions. It provides general-purpose parallel input/output expansion for most microcontroller families via the I2C-bus interface.

Characteristics: - 16-bit remote bidirectional I/O port - Low standby current consumption of 1 µA - Operating voltage range: 2.3 V to 5.5 V - Open-drain interrupt output - Active-low reset input - Noise filter on SCL/SDA inputs - No glitch on power-up - Internal power-on reset - Latched outputs with high-current drive capability for directly driving LEDs - Compatible with most microcontrollers - Available in TSSOP package

Package: TSSOP (Thin Shrink Small Outline Package)

Essence: The PCA9554DW is an essential component for controlling LED dimming and general-purpose I/O expansion in various electronic devices.

Packaging/Quantity: The PCA9554DW is typically sold in reels or tubes containing a quantity of 2500 units per package.

Specifications

• Supply Voltage Range: 2.3 V to 5.5 V
• Input Voltage Range: GND to VDD
• Output Voltage Range: GND to VDD
• Maximum Output Current: 25 mA per I/O pin
• Maximum Standby Current: 1 µA
• Maximum Operating Frequency: 400 kHz
• Operating Temperature Range: -40°C to +85°C

Pin Configuration

The PCA9554DW has a total of 20 pins arranged as follows:

```

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| | | 1 10 | | 2 11 | | 3 12 | | 4 13 | | 5 14 | | 6 15 | | 7 16 | | 8 17 | | 9 18 | |_______________| ```

Functional Features

• I2C-bus and SMBus compatible interface
• 16-bit bidirectional I/O port
• Individual direction control for each I/O pin
• Internal power-on reset
• Active-low reset input for device initialization
• Interrupt output with programmable polarity
• Noise filter on SCL/SDA inputs for improved performance in noisy environments
• Latched outputs with high-current drive capability for LED dimming applications

Advantages and Disadvantages

Advantages: - Low standby current consumption - Wide operating voltage range - Compatibility with most microcontrollers - Noise-filtered inputs for enhanced reliability - High-current drive capability for directly driving LEDs

Disadvantages: - Limited to 16-bit I/O expansion - Requires I2C-bus or SMBus interface support from the microcontroller

Working Principles

The PCA9554DW operates as an I/O expander by providing additional digital input/output pins to a microcontroller via the I2C-bus or SMBus interface. It allows the microcontroller to control and monitor external devices such as LEDs, switches, sensors, and other peripherals.

The device communicates with the microcontroller through the I2C-bus or SMBus, enabling bidirectional data transfer. The microcontroller can configure individual pins as inputs or outputs and read or write data to them accordingly. The PCA9554DW also features interrupt functionality, allowing the microcontroller to be notified of specific events or changes on the I/O pins.

Detailed Application Field Plans

The PCA9554DW finds applications in various fields, including but not limited to: - Backlight control in LCD displays - Keypad illumination in consumer electronics - LED dimming in automotive lighting systems - General-purpose I/O expansion in industrial automation - Control and monitoring of peripherals in smart home devices

Alternative Models

For users seeking alternatives to the PCA9554DW, the following models can be considered: - PCA9554APW: Similar specifications and features, available in TSSOP package - MCP23017: 16-bit I/O expander with similar characteristics, compatible with I2C-bus interface - MAX7313: 16-bit I/O expander with LED driver capabilities, available in TSSOP package

These alternative models offer similar functionality and can be used as replacements based on specific requirements and availability.

In conclusion, the PCA9554DW is a versatile I/O expander optimized for LED dimming applications. Its low standby current consumption, wide