3

MITSUBISHI <DIGITAL ASSP>

M35500AFP/BGP

FLD(VFD) CONTROLLER

Table. 1. Pin description

Function

• Applies voltage supplied to pull-down resistors.

• RC oscillator pins for system clock.

• Reset input pin for active “L”.

• Serial transfer is possible by inputting “L” signal.

• Clock for serial transfer is input.

• Read a clock twice with 2 MHz sampling clock and judge if it is a noise or not.

• Serial data is output.

• During reset it is in high-impedance state.

• Serial data is input.

• Read a clock twice with 2 MHz sampling clock and judge if it is a noise or not.

• Pin for ordinary output or digit output.

• Pin for digit output or segment output.

• Pin for segment output.

Output

Output

N-channel

open-drain

P-channel

open-drain

P-channel

open-drain

P-channel

open-drain

Pin

______

RESET

____

CS

Name

Power source

Pull-down

power source

Clock input

Clock output

______

RESET input

Chip select

Serial clock

Serial output

Serial input

Digit/Port

Digit/Segment

Segment

Input

Input

CMOS input

CMOS input

CMOS input

Noise filter

CMOS input

Noise filter

PORT BLOCK

Fig. 3. Port block diagram

PIN DESCRIPTION

(2) Digit pin

latch

Dimmer signal

(Note)

Shift signal from high-order

Shift signal to low-order

(3) Segment pin

latch

Dimmer signal

(Note)

Segment data

Serial input

Serial clock input

Noise filter

(1) Digit/Port pin

Digit/Segment pin

Data bus

Segment data

latch

Dimmer signal

(Note)

Shift signal from high-order

Shift signal to low-order

V High-breakdown-voltage P-channel transistor

Note: Dimmer signal is for setting the Toff time.

(5) CS pin

CS input

A-D conversion input

(7) A-D input

Noise filter

V

V

V