Rev A.3 – 2013/02 P2110-EVAL-02: Lifetime Power
®
Page 6
Energy Harvesting evelopment Kit for Battery Charging
www.powercastco.com
C arging Range
The line-of-sight range using the included transmitter and antennas is as follows:
ipole antenna: 20-25 feet
Patch antenna: 40-45 feet
C arge Current Calculation for THINERGY MEC
irect measurement of the THINERGY MEC is not available as access to the THINERGY battery terminals
was not provided to avoid possible damage to the cells. However, the charging current can be
calculated with the use of an oscilloscope with a voltage probe. Set the charging board to charge the
THINERGY MEC (JP2 to 4.1V, S1 to BATT, S2 to OFF). Attach a scope probe between the VBATT and GN
test points. Monitor the voltage on the scope, and you’ll notice two voltages over time, the open circuit
battery voltage, V
OC
, and the charging voltage, V
charge
which is set by JP2. Subtract V
OC
from V
charge
and
divide the result by the internal resistance of the battery and you will get the charging current for the
amount of time that the pulse-charger is on. The THINERGY MEC provided has an internal resistance of
approximately 35Ω.
Alternatively, charge current to the THINERGY MEC can be measured directly with the THINERGY A P
(not provided) using the 8-pin header P1 and the included cable (see below).
C arge Current Measurement
The charging current will only be shown for a small amount of time. To measure the current of an
external battery, set the Charging Board to charge the desired battery (JP2 to correct voltage, S1 to
BATT, S2 to OFF). The preferred method of measurement is to use an oscilloscope with a current probe
attached to battery terminal connection, XBATT or BT1. You can also place an ammeter in series with
the connection to XBATT or BT1, but depending on charging time, this method may not give accurate
results.
Wireless Sensor Demonstration
The Texas Instruments eZ430-RF2500 wireless development tool is included in the kit as a simple and
easy to use application demonstration. Please see the documentation from Texas Instruments for
software installation and operation. TI provides a free sensor demo PC application and the source code.
Powercast does not provide support for the eZ430-RF2500 kit.
To use the eZ430-RF2500 with the charging board:
• Install the Sensor Monitor software that comes with the eZ430-RF2500 kit
• Plug the eZ430-RF into a USB port, let windows search for drivers
• Launch the Sensor Monitor software. The access point node is shown middle of the window.
• Plug the THINERGY MEC into the Charging Board
• BAT-EVAL-01: S1 to BATT, S2 to VREG, S3 to 2.7V; P2110CSR-EVB: S1 to 4.1V
• Plug the eZ430-RF2500T target board into P2 on the Charging Board. A new node appear in the
Sensor Monitor window
• With the transmitter running, the THINERGY MEC will continue to pulse charge while the eZ430-
RF2500 continues to operate.
WARNING: O NOT ATTEMPT TO RECHARGE THE BATTERIES INCLU E WITH THE EZ430-RF2500 KIT AS
THEY ARE NOT RECHARGEABLE!
