PPM3 MKII Programmer - User Guide - V1.04 - 10
th
May 2008
71
4.9 Programmer and Target System are independently powered
4.9.1 Overview
In this scenario, the programmer is powered from a completely independent supply to the Target
System. The programmer must be powered via one of the
‘DC Power Connectors’
on the rear panel
at 9.0 – 12.0V. The Target System is powered from an external power supply in the range of 3.0 to
5.0V. The
Programmer_Vcc
output must
NOT
be connected to the
Target_Vcc
line in this scenario.
Fig. 4.9.1 Programmer and Target System are independently powered
Explanation of operation:
•
The programmer is always powered ON
•
The
‘Vcc Option Link’
is removed
•
LK1 connection
is removed (ie. Programmer and Target Vcc are disconnected)
•
The programmer must supply the same voltage as the
Target_Vcc
to the Programmer
‘I/O Level
Converter Circuitry’
.
•
The Target Power Supply should be switched OFF before the ISP cable is plugged into it
•
The programmer does not draw any current from the Target System during programming
•
When programming is complete, the Target System should be powered OFF and then the ISP
cable removed
Warning!
•
The voltage applied to the programmer via the ISP cable must be between 3.0 and 5.0V as
this voltage is used to drive the programmer I/O Stage. A 6V2 5W zener diode is internally
connected across the programmer supply to protect against over-voltage.
•
The Programmer and Target Vcc must be physically disconnected by cutting the Vcc signal
in the ISP cable if necessary.
Summary of Contents for PPM3 MK2
Page 1: ...User Guide...
