BQ25700A Datasheet, PDF (25/82 Pages) Texas Instruments – SMBus Multi-Chemistry Battery Buck-Boost Charge Controller With System Power Monitor and Processor Hot Monitor

www.ti.com
ICRIT
ILIM2
ILIM1
IVBUS
TOVLD
bq25700A
SLUSCQ8 – MAY 2017
TOVLD
TMAX
ISYS
IBAT
PROCHOT
Battery Discharge
Figure 12. Two-Level Adapter Current Limit Timing Diagram
8.3.8 Processor Hot Indication
When CPU is running turbo mode, the system peak power may exceed available power from adapter and battery
together. The adapter current and battery discharge peak current, or system voltage drop is indications that
system power are too high. The charger processor hot function monitors these events, and PROCHOT pulse is
asserted. Once CPU receives PROCHOT pulse from charger, it slows down to reduce system power. The
processor hot function monitors these events, and PROCHOT pulse is asserted.
The PROCHOT triggering events include:
• ICRIT: adapter peak current, as 110% of I_LIM2
• INOM: adapter average current (110% of input current limit)
• IDCHG: battery discharge current
• VSYS: system voltage on VSYS
• Adapter Removal: upon adapter removal (CHRG_OK pin HIGH to LOW)
• Battery Removal: upon battery removal (CELL_BATPRESZ pin goes LOW)
• CMPOUT: Independent comparator output (CMPOUT pin HIGH to LOW)
The threshold of ICRIT, IDCHG or VSYS, and the deglitch time of ICRIT, INOM, IDCHG or CMPOUT are
programmable through SMBus. Each triggering event can be individually enabled in REG0x34[6:0]. When any
event in PROCHOT profile is triggered, PROCHOT is asserted low for minimum 10 ms programmable in
0x33[4:3]. At the end of the 10 ms, if the PROCHOT event is still active, the pulse gets extended.
Copyright © 2017, Texas Instruments Incorporated
Submit Documentation Feedback
25