Bidirectional level conversion circuit

Level conversion circuit

Signal from chip 1 To chip 2

1. When chips 1 Output high level ,mos Pipe cut off , chip 2 The level is pulled up by the resistance to VCCB, chip B Receive high level
2. When chips 1 Output low level output ,mos The pipe is open , chip 2 The level is pulled down , chip 2 Input low level

When the signal from the chip 2 Transfer to the chip 1 when

1. When chips 2 Output high level ,mos The tube is in the cut-off state , chip 1 Pulled up by the resistance to VCCA, chip 1 Input high level VCCA;
2. When chips 2 Output low level ,mos Tubular Body diode Conduction , here MOS tube Vgs=VCCA-Vf, If at this time Vgs> Greater than Vgsth,MOS The pipe is open , Final chip 1 The input is low ;

The operating frequency is limited