• 状态
  • 已锁定 已锁定
  • 个回复 4 个回复
  • 名订阅用户 48 名订阅用户
  • 次查看 785 次查看
  • 用户 0 名在线用户
选项
选项
相关

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.

BQ79616-Q1: 应用问题请教

? ?
Prodigy 50 points
Part Number: BQ79616-Q1
Other Parts Discussed in Thread: BQ79616
  TI:
   
     请教BQ79616-Q1应用中的一些问题：
   1.上图是BQ79616-Q1规格书中194页的一个抓图 。对于（a）和（c）两种应用场景不太明白，我用BQ79616-Q1时只用到10个电芯，则此时多余的VC和CB引脚是按照（a）还是（b）来连接？
   2.BQ79616-Q1的温度测量可以用差分模式么？即用两个GPIO口来接NTC的两极。
   3.BBN和BBP用BUS BAR跨接时，BUS BAR电阻一般要求多大？测量的电流最大值大致是多少A？我的方案用的是钛酸锂电池BMS，其充电电流和放电电流较大，放电电流最大甚至有小几百安培，所以对电流特别关注。而BQ79616-Q1这个规格书中也没有这块儿的专门论述。
十分感谢支持
  • 0
    TI__Guru*** 130456 points

    您好

    1，根据手册上描述应该是按照a连接。

    It is recommended to populate the battery cells from bottom channels (both VC and CB channels) and up,
    leaving upper channels as unused channels if cell module size is smaller than the maximum channel size of the
    BQ7961x-Q1 device.

    2,3 正在询问更了解这款芯片TI 工程师，稍后回复。

  • 0 回复 Star Xu
    TI__Guru*** 130456 points

    您好，请参考下面内容。

    The temperature measurement is intended to be done ratiometrically to make sensing more accurate. The temperature can be approximated by testing what is the voltage drop across the NTC. To do this it is recommended to have a pull-up resistor to TSREF that is equal to the NTC resistance at nominal temperature, then the NTC at the GPIO pin. You could optionally add a low-pass filter to mitigate high-frequency noise. Trying to use the GPIO pins differentially would not work since all GPIO pins are programmed to be floating inputs with a weak pulldown resistor.

    As for the bus bar resistor, how are you connecting the busbar? Through the BBP/BBN pins or through the VC channels?

  • 0 回复 Star Xu
    Prodigy 50 points

    谢谢你的回复。我想将汇流条串接在最底端电池的CELL1的负极上，汇流条两端跨接BBN/BBP引脚。

  • 0 回复 ? ?
    TI__Guru*** 130456 points

    您好，So the BQ79616 does not do current measurement through the busbar pins. The BQ7965x family of devices (BQ79656, BQ79654, and BQ79652) does have the current sense capability with a shunt resistor. For these devices, the shunt resistor value should be chosen based on the maximum current and the absolute max voltage range (R_shunt*Imax<Vcs_max) as well as the maximum normal current and the recommended Vcs range (R_shunt*I_typical<Vcs_typical_max). Higher suitable resistance values lead to better ADC resolution but result in higher inefficiency, so that tradeoff would have to be made by the engineer(s).