µPD17P236

14

Data Sheet U14776EJ1V0DS00

3.2 Program Memory Writing Procedure

The program memory is written at high speed in the following procedure.

(1)

Pull down the pins not used to GND via resistor. Keep the CLK pin low.

(2)

Supply 5 V to the VDD pin. Keep the VPP pin low.

(3)

Supply 5 V to the VPP pin after waiting for 10

µs.

(4)

Set the program memory address 0 clear mode by using the mode setting pins.

(5)

Supply +6 V to VDD and +12.5 V to VPP.

(6)

Set the program inhibit mode.

(7)

Write data to the program memory in the 1-ms write mode.

(8)

Set the program inhibit mode.

(9)

Set the verify mode. If the data have been written to the program memory, proceed to (10). If not, repeat

steps (7) through (9).

(10) Additional writing of (number of times of writing in (7) through (9): X)

× 1 ms.

(11) Set the program inhibit mode.

(12) Input a pulse to the CLK pin four times to update the program memory address (+1).

(13) Repeat steps (7) through (12) up to the last address.

(14) Set the 0 clear mode of the program memory address.

(15) Change the voltages on the VDD and VPP pins to 5 V.

(16) Turn off power.

The following figure illustrates steps (2) through (12) above.

Write

Repeated X time

Verify

Additional write

Address

increment

MD3

MD2

MD1

MD0

D0-D7

CLK

GND

VDD

VDD

VDD+1

GND

VDD

VPP

VPP

Reset

Data input

Data output

Data input

Hi-Z

Hi-Z

Hi-Z

Hi-Z