SPI to I2C

CP2120 SPI-to-I²C Bridge Device and GPIO Port Expander

The CP2120 compact SPI-to-I²C bridge and general purpose port expander device can be easily added to a system to solve interface compatibility problems and add more GPIO when required.

The chip includes a 4-wire slave SPI bus, bridge control logic, a bidirectional I²C bus interface and eight general-purpose input/output (I/O) pins. An SPI master communicates with other I²C devices by instructing the CP2120 to send and receive I²C data traffic using the simple command set. The CP2120 can act as a master-transmitter and a master-receiver on the I²C bus. All I²C timing, addressing and arbitration is handled by the CP2120.

Features

4-wire SPI bus operates at frequencies up to 1 MHz
Fully-functional I²C master transmit and receive operation
I²C data at frequencies configurable up to 400 kHz
255 byte data receive and transmit buffers
Internal oscillator
2.4 to 3.6 volt operation
Active LOW interrupt output
5 volt tolerant I/O pins
8 general-purpose I/O pins

Applications

Status LEDs
Push button/keypad detection
LCD display control
EEPROM data storage
System monitoring

Technologies

Functions as an SPI slave to an I²C master
Allows a host with SPI-bus capability to communicate to an I²C bus

Documentation Expand All Collapse All

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Data Sheet (1)

Document Name	Description	Version	Last Updated
CP2120.pdf	CP2120 Data Sheet	0.4	4/23/2009

Data Short (1)

Document Name	Description	Version	Last Updated
CP2120_short.pdf	CP2120 Data Short	8.28.2006

Errata (1)

Document Name	Description	Version	Last Updated
CP2120Errata.pdf	CP2120 Errata	08.10.09	8/12/2009

User Guides (1)

Document Name	Description	Version	Last Updated
CP2120-EK.pdf	CP2120-EK User Guide	0.1

Application Notes (1)

Document Name	Description	Version	Last Updated
AN311.pdf	AN311: CP2120 Porting Guide	0.1

White Papers (1)

Document Name	Description	Version	Last Updated
Personal medical device market white paper.pdf	The Heartbeat behind Portable Medical Devices: Ultra-Low-Power Mixed-Signal Microcontrollers	0.1	9/3/2010

PCN (4)

Document Name	Description	Version	Last Updated
1110051 C-Pak as a Tape and Reel Supplier std.pdf	1110051 C-Pak as a Tape and Reel Supplier std
1005191A.pdf	MCU DFN/QFN/TQFN/TQFP Pkg Test Site Expand-ASECL, Grp2of2 Std
1005191.pdf	MCU DFN/QFN/TQFN/TQFP Pkg Test Site Expand-ASECL, Grp2of2, Std
1011021.pdf	MCU Fab(TSMC) & Assy(ASECL)Site Expansion Std

Design Resources

Product Matrix

Part Number		Available Documents	Communications	Internal Oscillator	Package	Other	RAM
CP2120		Data Sheet Data Short Errata	SPI to I2C	Yes	20-pin QFN	Voltage Monitor	512 (buffer RAM)

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Interface

Title Content
SPI-to-I²C Bridge Device and GPIO Port Expander

Features

Applications

Technologies