UPD75P3116 NEC, UPD75P3116 Datasheet - Page 27

• Manufacturer Part Number: UPD75P3116
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER
• Manufacturer: NEC

8. ONE-TIME PROM (PROGRAM MEMORY) WRITE AND VERIFY
The program memory contained in the PD75P3116 is a 16384 x 8-bit one-time PROM that can be electrically written one
time only. The pins listed in the table below are used for this PROM’s write/verify operations. Clock input from the X1
pin is used instead of address input as a method for updating addresses.
Caution Pins not used for program memory write/verify should be connected to Vss.
8.1 Operation Modes for Program Memory Write/Verify
When +6 V is applied to the V
mode. The following operation modes can be specified by setting pins MD0 to MD3 as shown below.
X: L or H
V
+12.5 V
PP
Operation mode specification
V
X1, X2
MD0 to MD3
D0/P60 to D3/P63
(lower 4 bits)
D4/P50 to D7/P53
(upper 4 bits)
V
PP
DD
V
+6 V
DD
Pin
DD
pin and +12.5 V to the V
MD0
H
L
L
H
MD1
L
H
L
X
Pin where program voltage is applied during program memory
write/verify (usually V
Clock input pins for address updating during program memory
write/verify. Input the X1 pin’s inverted signal to the X2 pin.
Operation mode selection pin for program memory write/verify
8-bit data I/O pins for program memory write/verify
Pin where power supply voltage is applied. Applies 1.8 to 5.5
V in normal operation mode and +6 V for program memory
write/verify.
MD2
H
H
H
H
PP
MD3
L
H
H
H
pin, the PD75P3116 enters the program memory write/verify
Zero-clear program memory address
Write mode
Verify mode
Program inhibit mode
DD
potential)
Function
Operation mode
PD75P3116
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