The model " PCA9548APWR " is a specific type of Integrated Circuit (IC) manufactured by NXP Semiconductors. It is an I2C multiplexer used to control multiple I2C buses through a single master controller, which allows for the expansion of I2C devices on a single bus.
Package Information
Package Type: QFN-24 (Quad Flat No-lead package with 24 pins)Pin Function and Specifications
This component has 24 pins in total, and here is the detailed explanation of each pin:
Pin No. Pin Name Function Description 1 VCC Power supply input (3.3V to 5V) 2 GND Ground pin 3 SCL0 I2C Clock for Bus 0 4 SDA0 I2C Data for Bus 0 5 SCL1 I2C Clock for Bus 1 6 SDA1 I2C Data for Bus 1 7 SCL2 I2C Clock for Bus 2 8 SDA2 I2C Data for Bus 2 9 SCL3 I2C Clock for Bus 3 10 SDA3 I2C Data for Bus 3 11 SCL4 I2C Clock for Bus 4 12 SDA4 I2C Data for Bus 4 13 SCL5 I2C Clock for Bus 5 14 SDA5 I2C Data for Bus 5 15 SCL6 I2C Clock for Bus 6 16 SDA6 I2C Data for Bus 6 17 SCL7 I2C Clock for Bus 7 18 SDA7 I2C Data for Bus 7 19 A0 Address pin 0 for I2C addressing 20 A1 Address pin 1 for I2C addressing 21 A2 Address pin 2 for I2C addressing 22 RESET Reset pin (active low) 23 INT Interrupt pin (active low) 24 VCC Power supply input (3.3V to 5V)Pin Function Description
The above table provides the primary function of each pin. For example:
SCLx and SDAx: These pins are for the clock (SCL) and data (SDA) lines for each of the 8 I2C buses supported by the multiplexer. These allow communication between the master device and peripheral devices across different I2C channels. A0, A1, A2: These are address selection pins. They help to set the I2C address of the chip. RESET: The reset pin is used to reset the device. This is typically used when the chip needs to be initialized or recovered from an error state. INT: The interrupt pin indicates when a communication error or other issue has occurred.Circuit Principle
The PCA9548APWR I2C multiplexer is a powerful tool for managing multiple I2C buses. By selecting which buses are active through the control register, it allows a master device (usually a microcontroller) to communicate with devices across multiple I2C buses without interference. The device uses 8 channels (SDA0-SDA7) and 8 corresponding clock lines (SCL0-SCL7). It facilitates the management of devices with conflicting addresses or expands the available I2C capacity.
20 FAQ - Common Questions
What is the PCA9548APWR used for? The PCA9548APWR is an I2C multiplexer used to control and expand I2C buses for devices with conflicting addresses or when more than one bus is needed.
What is the maximum voltage for the VCC pin? The VCC pin can accept voltages between 3.3V and 5V.
How many I2C buses does the PCA9548APWR support? It supports 8 I2C buses (SDA0-SDA7, SCL0-SCL7).
Can I use this component in a 5V system? Yes, it is compatible with both 3.3V and 5V systems.
What does the RESET pin do? The RESET pin is used to reset the device. It is active low, meaning it must be pulled low to reset.
How is the device addressed on the I2C bus? The device address is selected using the address pins A0, A1, and A2. These pins are used to configure the I2C address of the PCA9548APWR.
How many pins does the PCA9548APWR have? It has 24 pins in total.
What happens if I don't connect the RESET pin? If not connected, the device might not reset correctly when required, potentially causing erratic behavior.
How do I use the interrupt pin? The INT pin is used to signal an interrupt, typically indicating an error condition or an event that needs attention.
Can I use the PCA9548APWR with devices that have the same I2C address? Yes, the PCA9548APWR allows devices with the same I2C address to coexist on different buses.
Is there a specific order to connecting the SCL and SDA pins? The SCL (clock) and SDA (data) pins should be connected according to the I2C protocol for each bus.
Can I control the channels individually? Yes, the channels can be controlled individually through the I2C interface , allowing the user to select which bus is active.
What is the function of the address pins (A0, A1, A2)? The address pins determine the I2C address of the PCA9548APWR and help differentiate it from other devices on the bus.
What is the typical use case for the PCA9548APWR? It is used in situations where multiple I2C devices with the same address need to be controlled independently, or when additional I2C buses are required.
Is the PCA9548APWR compatible with any microcontroller? Yes, as long as the microcontroller supports I2C communication.
What is the current draw of the PCA9548APWR? It draws a minimal current when operating, but the exact current depends on the supply voltage and connected devices.
What is the significance of the INT pin? The INT pin provides a signal when an error or specific condition arises, and the master device can handle it accordingly.
What is the role of the VCC pin? The VCC pin is the power supply input for the chip, typically supplied with either 3.3V or 5V.
How many channels are available for I2C communication? There are 8 channels (SDA0-SDA7, SCL0-SCL7) available for I2C communication.
Can I use the PCA9548APWR for low-power applications? Yes, it is designed for low-power consumption while providing high functionality for I2C bus expansion.
These detailed explanations and FAQs should give you a comprehensive understanding of the PCA9548APWR.