Procedure For Use With Single-Cell Li-Ion Battery Or Simulated Battery Load; Charge Voltage And Current Regulation - Texas Instruments BQ24180 User Manual

Procedure for Use With Single-Cell Li-Ion Battery or Simulated Battery Load

4 Procedure for Use With Single-Cell Li-Ion Battery or Simulated Battery Load
4.1

Charge Voltage and Current Regulation

• Turn on PS#2 if simulated battery load is used and then PS#1.
• Software setup:
(a) Under Settings: Set Maximum Battery Regulation Voltage to 4.3 V via the pulldown window.
(b) Under Settings: Set Maximum Charge Current to 1.55 A via the pulldown window.
(c) Under Registers R0-R7: Click the Write button (W) by the Safety Limit (R6) in the lower right
corner. These values can only be changed on the first write command after having been powered
by the battery.
(d) Under Watchdog Timer: Check the Periodic Resets box, and set time to 20 Sec.
(e) On the Top Tool Bar: Select the Write On Change button to turn to ON.
(f) On the Top Tool Bar: Select the Auto Read button to turn to ON, and set the time to 10 Sec via
the pulldown window.
• Measure and verify the following conditions:
– Verify → Meter #1 is between 3.0 and 3.4 V. (If battery is used and its voltage is over the default
regulation voltage, then there is no charge current.)
– Verify → Meter #2 is between 9 mV and 15 mV (90 to 150 mA)
– Verify → Meter #3 is between 0.0 and 0.1 V.
– Verify → Input Current of PS#1 is between 80 mA and 100 mA.
– Verify → The STAT LED, on the UUT, is off (disabled).
This is an example of default mode where the input current limit is 100 mA, maximum, with a maximum
regulation of 3.5 V. If V
• Operation Changes Via Software:
(a) Under Settings: Set Battery Regulation Voltage to 4.0 V via the pulldown window.
(b) Under Settings: Set USB Host Current Limit to No Limit via the pulldown window.
(c) Under Settings: Set Charge Current (ICHG) to 1.15 A via the pulldown window.
(d) Under Controls: Check the Enable DCOUT box.
(e) Under Controls: Check the Enable STAT Function box.
• Measure and verify the following conditions:
– Verify → Meter #1 is between 3.2 V and 3.6 V.
– Verify → Meter #2 is between 80 mV and 120 mV (800 mA to 1200 mA).
– Verify → Meter #3 is between 3.2 V and 3.6 V.
– Verify → Input Current of PS#1 is between 75 mV and 100 mV (750 mA and 1000 mA).
– Verify → The STAT LED, on the UUT, is on (enabled).
This shows operation in fast charge constant current.
• Measure TP9 with ground sleeve of oscilloscope probe touching TP8 (GND). Set the oscilloscope to
200 ns/div and 2 V/div. The waveform must look like
must be 3 MHz ± 20%, the amplitude is +5 V ± 0.5 V and 0 V to –0.5 V and the duty cycle is 30 ± 10%
duty cycle.
• Uncheck the Watchdog Timer box and wait until the charge goes into default mode (less than 35
seconds), and observe that the charge current has dropped to ~125 mA (USB 100-mA input current
limit).
• Ground the TS pin by placing a short between J6-TS and J6-GND. This simulates a high-temperature
fault in default mode and shuts down the charge current in less than 35 seconds. To return to default
mode, remove the short.
A temperature fault in default mode shuts off the charge, whereas a temperature fault in normal
communication mode only notifies the host of a change in its register and does not disable the charge.
• See the data sheet for complete information on all specifications and functions.
• The software menu is intuitive and can be used to change many parameters.
• After evaluation, turn off PS#1 and then PS#2, if used.
6
bq24180 Evaluation Module
> 3.5 V, then the charge current goes to zero.
BAT
Copyright © 2010–2011, Texas Instruments Incorporated
Figure 4 with the following boundaries: frequency
SLUU419A – April 2010 – Revised April 2011
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