Modify circuit for Erase data W27Exxx ,W27Cxxx, SST27SFxxx
Figure 1. cut trace and add part
WinBond Chip (W27E512,W27E010,W27C010,W27C020)
Cut trace PCB U5A(
pin 12
) to ZIF32(
pin 26
) and add part
figure. 1
Settting Vpp ~= 15V (diode dorp 0.7V) Real voltage to taget chip = 15-0.7 = 14.3V
1N4148 = 0.7V, 1N4001 = 0.6V
parallel R15(2k2) with
resistor 15Kohm
for increase
Vpp(12.5V) to Vpe(14V)
figure. 2
Run program Eprom.exe
Put
CHIP W27xxxx,W27Cxxx
Select Device W27Exxx,W27Cxxx
short
JPx (close)
click Icon Erase (It will Erase and check blank)
move
JPx (open
) and
Resistor 15Kohm
check Blank again
load DATA
click Icon Program
End
SST Chip (27SF256/512/010/020)
Cut trace PCB U5A(
pin 12
) to ZIF32(
pin 26
) and add part
figure. 1
Settting Vpp ~= 12.75V (diode dorp 0.7V) Real voltage to taget chip = 12.75-0.7 = 12.05V
Run program Eprom.exe
Put
CHIP SST27SFxxx
Select Device SST27SFxxx
Short
JPx (close)
Click Icon Erase (It will Erase and check blank)
Move
JPx (open
)
Check Blank again
Load DATA
Click Icon Program
End
