Overview
The PCA9551PW,112 is an 8-bit I2C-bus LED driver with programmable blink rates, manufactured by NXP USA Inc. This device is designed to blink LEDs in I2C-bus and SMBus applications, reducing the need for repeated commands from the bus master and thus limiting bus traffic. The PCA9551 features an internal oscillator that allows for two fully programmable blink rates, making it ideal for applications where LED control needs to be automated without constant intervention from the microcontroller.
Key Specifications
| Parameter | Description |
|---|---|
| Package | TSSOP-16 |
| Operating Voltage | 2.3 V to 5.5 V |
| Output Sink Current | 25 mA per bit, 100 mA per package |
| Blink Rates | 0.148 Hz to 38 Hz (6.74 seconds to 0.026 seconds) |
| I2C-bus Clock Frequency | 0 Hz to 400 kHz |
| Addressing | Three hardware address pins allowing eight devices on the same bus |
| Reset | Active LOW hardware reset pin and Power-On Reset (POR) |
| ESD Protection | Exceeds 2000 V HBM, 150 V MM, and 1000 V CDM |
Key Features
- 8 LED drivers with programmable on, off, and flashing states
- Two selectable, fully programmable blink rates (frequency and duty cycle)
- Internal oscillator requiring no external components
- I2C-bus interface logic compatible with SMBus
- Internal power-on reset and active LOW reset input
- Noise filter on SCL/SDA inputs
- 8 open-drain outputs directly driving LEDs up to 25 mA
- Edge rate control on outputs
- No glitch on power-up and supports hot insertion
- Low standby current
- GPIO expansion for unused LED driver pins
Applications
The PCA9551 is suitable for various applications where automated LED control is necessary, such as:
- Industrial control systems
- Automotive systems requiring LED indicators
- Consumer electronics with LED displays
- Medical devices needing LED status indicators
- Any system requiring automated LED blinking without continuous microcontroller intervention
Q & A
- What is the primary function of the PCA9551?
The PCA9551 is an 8-bit I2C-bus LED driver with programmable blink rates, designed to control LEDs in I2C-bus and SMBus applications.
- How many blink rates can be programmed on the PCA9551?
The PCA9551 allows for two fully programmable blink rates.
- What is the range of the programmable blink rates?
The blink rates range from 0.148 Hz to 38 Hz (6.74 seconds to 0.026 seconds).
- What is the maximum output sink current per bit and per package?
The maximum output sink current is 25 mA per bit and 100 mA per package.
- Does the PCA9551 support GPIO expansion?
- What is the operating voltage range of the PCA9551?
The operating voltage range is from 2.3 V to 5.5 V.
- How many devices can operate on the same bus using the PCA9551?
Up to eight devices can operate on the same bus using the three hardware address pins.
- What type of reset does the PCA9551 have?
The PCA9551 has an active LOW hardware reset pin and a Power-On Reset (POR).
- Does the PCA9551 have ESD protection?
- What is the package type of the PCA9551PW,112?
The package type is TSSOP-16.
