Texas Instruments Chipcon CC2420DK, User Manual

Page: 11 / 32

SWRU045 Page 11 of 32
FPGA is turned on under software control when the USB controller has been properly
configured.
A diode prevents permanent damage if wrong polarity is applied to the non-regulated input.
There are two power connectors; a 3.5mm DC jack-type connector allows you to connect an
unregulated battery eliminator easily (the positive supply is on the center pin), and two 5-pin
terminal blocks can be used to connect either an unregulated or regulated power supply.
An amperemeter can also be connected in order to measure the DC current drawn by the
CC2420. Since the CC2420 has two voltage supplies (Core and I/O), there are separate
current measurement loops for these two supplies. If you are not going to measure the
currents, short-circuit jumpers must be connected between the terminals, otherwise the
Evaluation Module will not be supplied with power.
A
4-7V
0V
ExtI
III
IOI
0V
ExtC
IIC
IOC
A
0V
P2
P3
Figure 8: Power terminal block with amperemeters attached
Table 1: Power connector connections
Connector and pin Marking Description
P3 pin 1 4-7V Unregulated voltage in. Input to voltage regulators.
Equivalent with the DC jack input.
P3 pin 2 0V Circuit ground.
P3 pin 3 ExtI External I/O voltage. An externally applied voltage will
drive the I/O supply of the CC2420 (and the associated
FPGA pins) if the jumpers are set correctly.
P3 pin 4 III I/O supply current input. Insert an amperemeter
between this pin and the IOI pin to measure the current
drawn by the I/O supply of the CC2420.
P3 pin 5 IOI I/O supply current output. Insert an amperemeter
between this pin and the III pin to measure the current
drawn by the I/O supply of the CC2420.
P2 pin 1 0V Circuit ground.
P2 pin 2 0V Circuit ground.
P2 pin 3 Ext C External core voltage. An externally applied voltage
that will drive the core supply of the CC2420 if the
jumpers are set correctly.
P2 pin 4 IIC Core voltage current input. Insert an amperemeter
between this pin and the IOC pin to measure the
current drawn by the core supply of the CC2420.
P2 pin 5 IOC Core voltage current output. Insert an amperemeter
between this pin and the IIC pin to measure the current