IIC bus interface electrostatic protection circuit

Abstract

The invention discloses an IIC bus interface electrostatic protection circuit which is characterized in that SCL and SDA two lines of an IIC bus are respectively provided with a grounded TVS diode; and when static electricity is conducted to an IIC bus interface, the IIC bus interface generates a high voltage to the earth, and the TVS diode can immediately work a protection function to prevent the interface from being damaged due to rising of IIC bus interface voltage, and thus the circuit plays an electrostatic protection function on the IIC bus interface.

Description

technical field [0001] The invention relates to an electronic circuit with an IIC bus interface, in particular to an electrostatic protection circuit for the IIC interface of a component. Background technique [0002] At present, a large number of peripheral devices with IIC interfaces are used in embedded systems to communicate with microprocessors, such as EEPROM chips, Flash chips, clock chips, etc., all of which provide IIC bus interfaces. In practical applications, the IIC interface of the microcontroller (MCU) is connected to the IIC interface of the peripheral device to realize the master-slave communication function. [0003] At present, the anti-interference miss of external components is very scarce. Usually, the measure of wrapping the IIC communication line with pull-up resistors, decoupling capacitors and PCB ground network is mainly used to increase the anti-interference ability, such as figure 1 . However, measures such as setting pull-up resistors, decoupli...

AI Technical Summary

Problems solved by technology

Even after the above measures are taken, in actual use and during electrostatic discharge tests, it is found that the IIC interface of the MCU or peripheral devices is often damaged by static electricity

And this kind of damage is usually permanent, even if the power is turned on again after a power failure, it cannot be recovered

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