System Overview
The CP2120 is a highly-integrated SPI-to-I2C Bridge Controller with an SPI interface that provides a simple and reliable method for communicating with I2C devices. The CP2120 includes a 4-wire serial peripheral interface (SPI), a serial I2C interface, 256 byte data buffers, an internal oscillator, eight input/output port pins, and one pin configurable as an edge-triggered interrupt source in a compact 4x4 package. No external components other than pull-up resisters on the I2C pins are required. The SPI Master controls the CP2120 across the SPI interface using a command set that governs all CP2120 configuration and operation.

Single Chip SPI to I2C Transfer
   ● Integrated clock; no external clock required
   ● On-Chip Voltage Monitor

Slave Serial Peripheral Interface (SPI)
   ● Up to 1.0 Mbit/s Transfers
   ● Configurable to Least Significant Bit or Most Significant
      Bit first byte transfers
     
I2C Master Interface
   ● Operates at configurable rates up to 400 kHz
   ● 255 RX and TX Data Buffers

Input and Output Port Pins
   ● 8 Pins Configurable as Push-Pull or Open-Drain
   ● 1 Pin Configurable as an edge-triggered interrupt
      source
   ● All pins 5 V Tolerant
   ● INT active low interrupt pin

Supply Voltage of 2.7 V to 3.6 V
   ● Typical operating current: 6.4 mA

Package
   ● Pb-free 20-pin QFN