CP2120-GMR

Overview

The CP2120-GMR is a single-chip SPI to I2C bridge controller manufactured by Silicon Labs. It operates within a supply voltage range of 3.0 V to 3.6 V, with a typical operating current of 3.8 mA at 3.0 V. The device supports SPI slave transfers up to 1.0 Mbit/s and I2C master operations at configurable rates up to 400 kHz. It features an integrated internal oscillator, eliminating the need for external clock components. The component includes 255-byte RX and TX data buffers and eight configurable GPIO pins. It is housed in a Pb-free 20-pin QFN package and functions within a specified operating temperature range of -40 °C to +85 °C.

Feature Summary

• Integrates a four-wire SPI slave interface for communication with a host SPI master.
• Functions as an I2C master interface capable of driving SCL and reading SDA on connected devices.
• Includes eight general-purpose input/output pins configurable as push-pull or open-drain outputs.
• Features an edge-triggered interrupt source pin (EINT) and an active-low interrupt indicator (INT).

Applications

• Converting SPI-based system architectures to communicate with I2C peripheral devices.
• Expanding I/O capabilities in embedded systems through configurable GPIO ports.
• Interfacing with SMBus-compatible devices using built-in timeout detection features.

Procurement Notes

Verify that the specific ordering suffix matches the required package variant and environmental compliance standards. Confirm that the intended application environment falls within the specified electrical and thermal operating limits defined in the datasheet. Ensure pull-up resistor values are calculated correctly for the target I2C bus capacitance to maintain signal integrity.

Selection Notes

Select this component when an SPI-to-I2C translation layer is required without external logic. Consider the 20-pin QFN package constraints for PCB layout. Evaluate the GPIO configuration needs against the available eight pins. Verify that the maximum SPI clock speed requirements do not exceed the device's timing specifications under the chosen system clock conditions.

Part Context

The CP2120 belongs to Silicon Labs' family of I/O controller interface ICs designed for serial protocol bridging. It serves as a dedicated bridge solution between SPI masters and I2C slaves, distinct from USB-to-UART or other interface controllers in the manufacturer's portfolio. The device simplifies system design by integrating necessary control logic and buffers into a compact form factor.

Replacement Considerations

Public documentation indicates the CP2120 is marked 'Not Recommended for New Designs'. No specific replacement part numbers are confirmed in the provided source material. Designers should consult official Silicon Laboratories notices for current alternative recommendations.