ML9352 datasheet(21/53 Pages) OKI

21 / 53 page

PEDL9352-01

OKI Semiconductor

ML9352

21/53

Display timing generator circuit

This circuit generates the timing signals for the line address circuit and the display data latch circuit from the

display clock. The display data is latched in the display data latch circuit and is output to the anode driver output

pin in synchronization with the display clock. The read out of the display data to the organic EL drive circuits is

completely independent of the display data RAM access from the MPU. As a result, there is no bad influence such

as flickering on the display even when the display data RAM is accessed asynchronously during the organic EL

display. Also, the internal cathode timing is generated by this circuit from the display clock.

Common output state selection circuit (see Table 5)

Since the COM output scanning directions can be set using the common output scan direction select command in

the ML9352, it is possible to reduce the IC placement restrictions at the time of assembling organic EL modules.

Table 5

State

COM Scanning direction

Normal Display

COM0

→ COM31

Reverse Display

COM31

→ COM0

* When the number of display lines is 32.

Organic EL Drive circuits

The anode driver circuit employs the constant current system and the cathode driver circuit employs the push-pull

system. The anode output current is set by the voltage applied to VEL pin, or output voltage of the built-in voltage

regulator, and the external resistors connected to the REL1 and REL2 pins.

IELA = VEL/REL

(Here, IELA: Anode output current; VEL: Voltage applied to VEL pin or the output voltage of built-in voltage

regulator; and REL: External resistors connected to the REL1 and REL2 pins.)

Selection between the voltage applied to the VEL pin and the output voltage of built-in voltage regulator is by the

ELSEL pin. Similarly, selection of REL1 pin or REL2 pin is by the external resistor switching command for adjusting

anode output current.

When in the power save mode, all operations of the built-in voltage regulator and the organic EL drive circuits are

stopped. And the anode and cathode drivers’ outputs go to the VSS level.

ML9352 Datasheet(PDF) 21 Page - OKI electronic componets