HD66100F

115

Block Functions

LCD Drive Circuits

Select one of four levels of voltage V1, V2, V3, and V4 for driving a LCD and transfer it to the output

terminals according to the combination of M and the data in the latch circuit.

Latch Circuit

Latches the data input from the bidirectional shift register at the fall of CL1 and transfer its outputs to the

LCD drive circuits.

Bidirectional Shift Register

Shifts the serial data at the fall of CL2 and transfers the output of each bit of the register to the latch

circuit. When SHL = GND, the data input from DI shifts from bit 1 to bit 80 in order of entry. On the

other hand, when SHL = V

the register is latched to be output from DO at the rise of CL2.

LCD drive outputs

Latch circuit

Shift register

12

79 80

12

79 80

CL1

CL2

DI

DO

SHL = GND

Y1 Y2

Y79 Y80

LCD drive outputs

Latch circuit

Shift register

12

79 80

12

79 80

CL1

CL2

DO

DI

Y1 Y2

Y79 Y80

Figure 3 Relation between SHL and the Shift Direction