KISSEPROM
(Keep It Simple and Strong):
Eprom Programmer for 27Cxx
Family
(and more)
and a short tutorial
about Eprom
Hardware
(Power Supply Board)
Intro Eproms Hardware Software
The
power supply module gives +5v, 5/6,3v (switched through the software), and 12,5 - 21 - 25V
(for programming);
I've build a separate power supply so I can use it also for other thing, other
programmers etc.;
You can also use a commercial supply or your own ;
Schematics are quite simple: a transformer give 25v rectified
by the diode bridge;
now we have 3 point (going to 3 different IC):
the first LM7805 (on metal dissipator) give out +5V for the base board (CD4040, transistor ecc.)
the LM317 give out +12,5/21/25 V (selected through a manual switch) for eprom programming;
the
last 7805 give out +5/6,3V for eprom supply; in read mode TR1 (E-C) is
closed and M pin of IC is directly connected to the ground; in this
condition we have +5v;
when programming TR1
is open and M pin of IC is connected to the ground through D1, D2 making the
outpu higher of 1,3v
(0,6-0,7V for each diode); in this condition we have 5+1,3=+6,3V
output.
On the frontal panel there's a ON/OFF switch, Vpp selector , leds and a DIN
socket;
Note that the box cames from a broken CD-Rom (it was Christmas holiday, so all
shop closed).
Continue with KissEprom Software
73 de iz7ath, Talino Tribuzio