2. 12 V is applied to the V
PP
and mode MD2 pins when programming or erasing flash memory.
When these pins are pulled up to the V
CC
line in normal operation, diodes should be inserted to
prevent reverse current from flowing to the V
CC
line when 12 V is applied.
Note: In normal operation, if the mode MD2 pin to which 12 V is applied is to be set to 0, it
should be pulled down with a resistor.
A sample circuit is shown figure 18-32.
Figure 18-32 Example of Mounting Board Design
(Connection to Adapter Board—When V
PP
Pin and Mode Pin Settings Are 1)
630
V
PP
H8/3048F
MD2
0.01
µ
F 1.0
µ
F
V
CC
V
CC
0.01
µ
F 1.0
µ
F
12 V
12 V
mode
pin
Adapter board
User system
V
PP
pin
Mode pin
www.DataSheet4U.com