• State Resolved
  • Locked Locked
  • Replies 10 replies
  • Answers 4 answers
  • Subscribers 63 subscribers
  • Views 354 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Original question:

BQ25895 VBUS/PMID/VSYS interaction

BQ25895: Strange behaviour of my BQ25895

ju zhang56
Prodigy 130 points
Part Number: BQ25895

Hi,

   I met a very strange problem. I use STM8 to control BQ25895 and all things worked well.

But when the battery was full and still leave the charger plugged for about 8 hours, the charger will not charging any more until the battery was absolutely drained.

HVDCP_EN was reset to 0 automatically meanwhile.

    What's the problem?

  • 0
    TI__Guru 57831 points

    Hi,

    Could you please provide the followings for both normal and abnormal conditions?

    1. What are the test conditions such as VBUS (voltage at VBUS pin), IVBUS, VBAT (voltage at BAT pin), IBAT, VSYS, ISYS ?

    2. What are all the register values?

    Thanks,

    Ning.

  • 0 in reply to Ning T
    Prodigy 130 points

    discharge（normal）

    DisCharge!

     

     

     

    BAT_volt:4104

     

    SYS_vlot:4124

     

    Charge Current:0

     

    VBUS_Volt:2600

     

    REG00:59

     

    REG01:5

     

    REG02:189

     

    REG03:48

     

    REG04:36

     

    REG05:19

     

    REG06:158

     

    REG07:205

     

    REG08:3

     

    REG09:64

     

    REG0A:163

     

    REG0B:226

     

    REG0C:0

     

    REG0D:152

     

    REG0E:90 92 94

     

    REG0F:91 94

     

    REG10:63 62

     

    REG11:0

     

    REG12:0

     

    REG13:59

     

    REG14:57

     

    Charging（normal）

    VBUS Attached

    Power Good

    Charge_done

    Charging!

    Adjustabe High Voltage DCP

    Fast Charging

    BAT_volt:4464

    SYS_vlot:4484

    Charge Current:1950

     

    VBUS_Volt:11700

     

    REG00:28

     

    REG01:5

     

    REG02:189

     

    REG03:48

     

    REG04:36

     

    REG05:19

     

    REG06:158

     

    REG07:205

     

    REG08:3

     

    REG09:64

     

    REG0A:163

     

    REG0B:150

    100: Adjustable High Voltage DCP (MaxCharge) (1.5A)/ 10 – Fast Charging

    REG0C:0

     

    REG0D:152

     

    REG0E:108

     

    REG0F:109

     

    REG10:63

     

    REG11:219

     

    REG12:39

     

    REG13:22

     

    REG14:57

    Charging（abnormal）

    Charging!

    USB DCP

    Fast Charging

     

    BAT_volt:4264

     

    SYS_vlot:4264

     

    Charge Current:0

     

    VBUS_Volt:5000

     

    REG00:63

     

    REG01:5

     

    REG02:181

    0 – Disable HVDCP handshake

    REG03:148

    Battery Load (IBATLOAD)Enable/0 – OTG Disable

    REG04:17

     

    REG05:19

     

    REG06:158

     

    REG07:205

     

    REG08:3

     

    REG09:64

     

    REG0A:163

     

    REG0B:118

    011: USB DCP (3.25A)/ 10 – Fast Charging

    REG0C:0

     

    REG0D:152

     

    REG0E:98

     

    REG0F:98

     

    REG10:63

     

    REG11:152

     

    REG12:0

     

    REG13:128

     

    REG14:57

  • 0 in reply to ju zhang56
    TI__Guru 57831 points

    Hi,

    REG13=80H indicate VINDP. Please check VBUS pin voltage and see if it drops too low.

    Thanks,

    Ning.

  • 0 in reply to Ning T
    Prodigy 130 points

    VBUS dropped from 12V to 5V，but not TOO low as my thougt.

  • 0 in reply to ju zhang56
    TI__Guru 57831 points

    Hi,

    REG0D=98H indicates VINDPM setting=5.0V. If VBUS pin voltage drops to 5V, VINDPM will be triggered.

    Thanks,

    Ning.

  • 0 in reply to Ning T
    Prodigy 130 points

    Oh~~~

    I see!

    Thank you very much!!

  • 0 in reply to Ning T
    Prodigy 130 points

    Hi, Ning.

    I met another problem!

    We use INT pin and have interrupt process in our MCU.

    When the Charging Termination condition was met, the BQ25895 sent Int to MCU continiously, and never stop. This made our MCU programme to be crazy.

    Iwant to know WHY and HOW to stop these annoying INTs？

  • 0 in reply to ju zhang56
    TI__Guru 57831 points

    Hi,

    Referring to 8.2.9.2 Interrupt to Host (INT) on the d/s, The following events will generate 256-µs INT pulse. Please check if any other conditions trigger the INT pulses.

    • USB/adapter source identified (through PSEL or DPDM detection, with OTG pin) • Good input source detected – VBUS above battery (not in sleep) – VBUS below VACOV threshold – VBUS above VVBUSMIN (typical 3.8 V) when IBADSRC (typical 30 mA) current is applied (not a poor source) • Input removed • Charge Complete • Any FAULT event in REG0C

    Thanks,

    Ning.

  • 0 in reply to Ning T
    Prodigy 130 points

    These Ints come continiously if and only if the Charge Complete condition met. 

  • 0 in reply to ju zhang56
    TI__Guru 57831 points

    Hi,

    Please provide

    1. The test conditions such as VBUS (voltage at VBUS pin), IVBUS, VBAT (voltage at BAT pin), IBAT, VSYS, ISYS.

    2. All register values right before and after INT pulse when charge complete.

    Thanks,

    Ning.