ISPJUNO - Portable ISP Programmer - User Guide V0.84 – 17/04/20
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4.3.3 Programmer signal IO (line driver) voltage range
The programmer
‘signal IO (line driver) voltage range’
defines the voltage swing of the programmer
‘IO signals’
.
When the programmer is set to
‘Programmer is powering the target system’
, then the programmer
‘Line Driver voltage’
will be set to the same value as specified in the project. This means that the IO
signals used to actually program the target device / IC will now swing between 0V and the selected
‘Target Voltage’ as shown in the table below….
Programmer
TVCC output
voltage
(V)
Logic 0
voltage
(V)
Logic 1
voltage
(V)
3.0
0
3.0
3.3
0
3.3
4.7
0
4.7
5.0
0
5.0
Warning!
It is possible to damage the Target Device / IC by setting the
‘Programmer TVCC voltage’
to a
value higher than the recommended voltage for the Target IC / Device.
If programming a device with a
‘Maximum allowed voltage’
of 3.3V, do NOT set the
‘Programmer
TVCC voltage’
to a value higher than 3.3V.
4.3.4 Programmer power supply - current limit
There is no
‘current measurement’
on this programmer.
The
‘programmer controlled – target power supply’
will automatically start to current-limit at
approximately 250 mA to prevent damage to the programmer.