Quick Start Procedure - Linear Technology DC1007C Manual

QUICK START PROCEDURE

8. Discharge the battery to 2.5V. If charger mode is on,
observe it is charging in trickle charge mode and
the charge current is 50mA. As the battery voltage
increases above 2.85V observe that the charger goes
into full constant current mode. Observe that VOUT
stays above 3.6V when the input current limit is not
exceeded. Remove the NTC jumper on JP2. Observe
the CHRG LED slow blinking rate. Also observe the
35KHz pulse with varying duty cycle between 4.7%
and 95.3% on the CHRG terminal with an oscilloscope.
Reinstall the NTC jumper.
9. Increase the VOUT load and observe when the input
current starts to limit (V
current limit is reached, VOUT drops from 300mV
= 1.188V). When input
CLPROG
DEMO MANUAL DC1007C
above the BAT voltage to 15mV below the BAT volt-
age and the additional load transitions to the battery
through the ideal diode. Due to the high efficiency of
the switching regulator, the charge and load current
may be significantly above the input current depending
on the voltage on the BAT pin.
10. Repeat step 9 with different current limit modes.
11. Set the VBUS input supply to 5V. Observe the battery
current as the battery voltage increases above 4.1V.
The charge current starts to decrease as the battery
voltage increases towards 4.2V.
See the latest LTC4088 data sheet for more information
on how this part performs.
dc1007cf
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