CHARGE-TRANSFER CODED VOLTAGE GENERATOR, ANALOG-DIGITAL CODER AND DECODER COMPRISING SUCH A GENERATOR

摘要

Successive two-trip traversals of charges between gates G0 and G2 make it possible to obtain beneath gates G1 and G2 quantities of charges equal to QR, QR/2, QR/22 . . . QR/2i. A readout device for reading charges and connected to gates G2 and G4 generates voltages VR and VRi=a0xVR+a1xVR/2+ . . . +ai-1xVR/2i-1+VR/2i which are compared with a voltage sample Vx to be coded in order to determine by successive approximations the coefficients a0 . . . an which are equal to 0 or to 1 such that Vx=a0xVR+a1xVR/2+ . . . +anxVR/2n. Depending on the value of ai, each quantity of charges QR/2i stored beneath gate G1 is removed beneath diode De or stored beneath gate G3 and then transferred beneath gate G4.