Hardware Description
3-16
AVR STK500 User Guide
1925C–AVR–3/03
3.8.1
Target V
CC
Settings,
VTARGET
VTARGET controls the supply voltage to the target AVR microcontroller sockets. It can
either be controlled from AVR Studio or supplied from an external source. If the VTAR-
GET jumper is mounted, the on-board supply voltage is connected. The on-board
supply voltage can be adjusted to 0 - 6V from AVR Studio. Always verify the respective
datasheet for the AVR device operating voltage before adjusting VTARGET voltage.
Using the on-board supply voltage, approximately 0.5A can be delivered to the target
section. See “Appendix A” in Section 10.
If the VTARGET jumper is disconnected, target V
CC
must be supplied from an external
source at one of the VTG pins on the PORT headers. Figure 3-21 explains VTARGET
jumper options.
When using an external source for VTARGET, the user must control that VTARGET is
at a higher voltage level than AREF (analog reference voltage). Always connect com-
mon ground (GND) when using an external VTARGET voltage.
Figure 3-21.
VTARGET Jumper Options
The STK500 master microcontroller controls the target voltage using the internal PWM.
Figure 3-22 shows the internal connection of the VTARGET signal.
Figure 3-22.
VTARGET Connection
Note:
The green LED will light when there is a voltage available on the VTG NET. It’s
impossible to use the debug or programming area of STK500 without VTG.
VTARGET
AREF
VTARGET
AREF
Jumper Mounted
Jumper not Mounted
On-board VTARGET supply connected (default)
On-board VTARGET supply disconnected
Master
MCU
VTARGET
PWM
VTG NET
Green LED
Jumper
Voltage
Regulator
10 - 15V
VIN
0 - 6V
Wr
Rd
ADC
Содержание AVR STK500
Страница 1: ...STK500 User Guide ...
Страница 2: ......
Страница 38: ...Hardware Description 3 28 AVR STK500 User Guide 1925C AVR 3 03 ...
Страница 40: ...Installing AVR Studio 4 2 AVR STK500 User Guide 1925C AVR 3 03 ...
Страница 52: ...In System Programming of an External Target System 6 2 AVR STK500 User Guide 1925C AVR 3 03 ...
Страница 56: ...Technical Support 8 2 AVR STK500 User Guide 1925C AVR 3 03 ...
Страница 60: ...Appendix A 10 2 AVR STK500 User Guide 1925C AVR 3 03 ...