US 12,147,378 B2
I2C wakeup circuit, wakeup method and electronic device
Ze He, Xi'an (CN)
Assigned to GIGADEVICE SEMICONDUCTOR (XIAN) INC., Xi'an (CN)
Filed by GIGADEVICE SEMICONDUCTOR (XIAN) INC., Xi'an (CN)
Filed on Dec. 10, 2022, as Appl. No. 18/078,938.
Claims priority of application No. 202210033143.7 (CN), filed on Jan. 12, 2022.
Prior Publication US 2023/0222086 A1, Jul. 13, 2023
Int. Cl. G06F 13/42 (2006.01); H03K 5/125 (2006.01)
CPC G06F 13/4291 (2013.01) [H03K 5/125 (2013.01); G06F 2213/0016 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An I2C wake-up circuit, configured to wake up an I2C communication module in a slave for I2C communication when an internal clock circuit of the slave is turned off, and comprising:
a clock wake-up circuit, configured to send a clock wake-up signal to the internal clock circuit in response to detecting a start signal from a master on a serial clock line SCL and a serial data line SDA, wherein detecting the start signal corresponds to detecting the SCL signal being high while the SDA signal goes low; and
a signal holding circuit, configured to detect the signal on SCL after the clock wake-up circuit detects the start signal and continuously pull down the SCL when detecting the SCL signal is pulled low by the master to make the master wait by holding the serial data line SDA in a state of not transmitting address information until a clock signal sent by the internal clock circuit that is awakened is received.