Segger J-Link User Manual page 154

152
8.1.2.1 Target board design
We strongly advise following the recommendations given by the chip manufacturer.
These recommendations are normally in line with the recommendations given in the
table Pinout for SWD on page 150. In case of doubt you should follow the recommen-
dations given by the semiconductor manufacturer.
JTAG connector
J-Link
* Optional to supply the target board from J-Link.
8.1.2.2 Pull-up/pull-down resistors
A pull-up resistor is required on SWDIO on the target board. ARM recommends 100
kOhms.
In case of doubt you should follow the recommendations given by the semiconductor
manufacturer.
8.1.2.3 Target power supply
Pin 19 of the connector can be used to supply power to the target hardware. Supply
voltage is 5V, max. current is 300mA. The output current is monitored and protected
against overload and short-circuit.
Power can be controlled via the J-Link commander. The following commands are
available to control power:
Command
power on
power off
power on perm
power off perm
Table 8.4: Command List
J-Link / J-Trace (UM08001)
Typical target connection for SWD
19*
5V supply
1
VTref
7
SWDIO
9
SWCLK
13
SWO
15
RESET
20
GND
Switch target power on
Switch target power off
Set target power supply default to "on"
Set target power supply default to "off"
CHAPTER 8
19
1
7
9
13
15
20
Explanation
© 2004-2009 SEGGER Microcontroller GmbH & Co. KG
Target interfaces and adapters
Target board
Voltage
Regulator
VCC
SWDIO
SWCLK
CPU
SWO
nRST
GND
VCC