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2 Test Summary
2.1 Input/Output and Jumper Connections
2.2 Test Procedure Using Single-cell Li-ion Battery
Test Summary
This section describes:
• Input/Output and Jumper Connections
• Test Procedure Using Single Cell Li-ion Battery
• Alternative Test Procedures (Without Battery)
• Required Equipment
• Test Equipment Setup
• Test Procedure
The bq24085/6/7/8 EVM board requires a 5-VDC, 1-A power source to provide input power and a
single-cell Li-ion or Li-polymer battery pack. The test setup connections and jumper setting selections are
configured for a stand-alone evaluation but can be changed to interface with external hardware such as a
microcontroller.
Table 2. I/O and Jumper Connections
Jack Connect To:
J1-DC+ Power supply positive, preset to 5 VDC, 1-A current limit.
J1-DC– Power supply ground
J2-BAT+ Positive battery pack terminal
J2-BAT– Negative battery pack terminal
J2-TS NC
J2-BAT– NC
J3-STAT1 External hardware if J4-EXT is jumpered (Not jumpered from factory)
J3-STAT2 External hardware if J5-EXT is jumpered (Not jumpered from factory)
J3-DC– Return for J3 signals
J3-PG External hardware if J6-EXT if jumpered (Not jumpered from factory)
JMP1 (Jumper) LED connection
JMP2 (Jumper) LED connection
JMP3 (Jumper) LED connection (bq24085, bq24086, and bq24088). CE - without jumper defaults low - Charge Enable, with
Jumper - Charge Disable
JMP4 (Jumper) TMR enable with jumper installed
Set up the evaluation board as previously described in Table 2 , making the necessary I/O connections
and jumper selections. Prior to test and evaluation, it is important to verify that the maximum IC power
dissipation (P
(MAX)
= 1.5 W) is not exceeded.
1. Turn on the power supply, which was preset to 5 VDC, and 1 A for the current-limit setting.
2. The bq24085/6/7/8 enters preconditioning mode if the battery is below the V(LOWV) threshold. In this
mode, the bq24085/6/7/8 precharges the battery with a low current (typically IO(CHG) /10 = 0.4A/10 =
40 mA) until the battery voltage reaches the V
(LOWV)
threshold or until the precharge timer expires. If
the timer expires, then the charge current is terminated and the bq24085/6/7/8 enters fault mode. Both
LEDs turn off when in fault mode. Toggling input power or battery replacement resets fault mode.
3. Once the battery voltage is above the V
(LOWV)
threshold, the battery enters fast-charge mode. This
EVM is programmed for 0.4 A of fast-charging current.
4. Once the battery reaches voltage regulation (4.2 V), the current tapers down as the battery reaches its
full capacity.
5. The battery remains at the fast charge mode until either the charge timer expires or the charge
termination current threshold is reached.
2 bq24085/6/7/8 Evaluation Module SLUU305 – March 2008
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