TI中文支持网最近在用BQ24195做项目，发现如下问题；
1、在升压模式工作切换到充电模式后，STAT指示灯亮起，但是不能立马进入充电状态（电池端电流表无充电电流）；
表现如下：CEpin 一直是拉低的状态，然后检测OTG被硬件拉低后关闭BOOST模式，使能CHARG BAT模式，这时候电池无充电电流；但是此时如果拔掉电池再插上或者单片机重启后(单片机启动过程中执行了初始化代码)就可以立即进入充电状态（电池端电流表出现充电电流）；
2、在数据手册种看到使能充电条件如下：
A new charge cycle starts when the following conditions are valid:
• Converter starts
• Battery charging is enabled by I2C register bit (REG01[5:4]) = 01 and CE is low
• No thermistor fault on TS1 and TS2
• No safety timer fault
• BATFET is not forced to turn off (REG07[5])
其中条件2 3 4 5均以满足，但是不清楚条件1如何启动？请求TI技术解答，谢谢！
以下是BQ24195初始化代码:
/* Set REG00 EN_HIZ = Disable; VINDPM = 4.2V; IINLIM = 3A */
BQ24195_Write_Register(0x00, 0x27); // 0 0 1 0 0 1 1 1
/* Set REG04 VREG = 4.2V; BATLOWV = 3.0V; VRECHG = 100mV */
BQ24195_Write_Register(0x04, 0xB2); // 1 0 1 1 0 0 1 0
/* Set REG02 ICHG = 2.048A; Reserved = 0; FORCE_20PCT = 0 */
BQ24195_Write_Register(0x02, 0x60); // 0 1 1 0 0 0 0 0
/* Set REG05 EN_TERM = 1; TERM_STAT = 0; WATCHDOG = Disable; EN_TIMER = Enable; CHG_TIMER = 5hours; Reserved = 0 */
BQ24195_Write_Register(0x05, 0x88); // 1 0 0 0 1 0 0 0
/* Set REG01 REGISTER RESET = 0; WATCHDOG TIMER RESET = 0; CHG_CONFIG = CHARGE BAT; SYS_MIN = 3.5V; Reserved = 0 */
BQ24195_Write_Register(0x01, 0x1B); // 0 0 0 1 1 0 1 1
Johnsin Tao：
Hi
可能是操作顺序上的问题
先将OTG pin HIGH and REG01[5:4] = 10 改过来，改为充电模式下设置。 再设置电流限制，CE拉低。
hugang Ding1：
回复 Johnsin Tao:
谢谢您的解答；刚才仔细查看数据手册，发现了问题；数据手册种有这么一段话；
8.3.3.5 Charging Safety TimerThe bq24195L, bq24195 has safety timer to prevent extended charging cycle due to abnormal battery conditions.In default mode, the device keeps charging the battery with 5-hour fast charging safety timer regardless ofREG05[2:1] default value. At the end of the 5 hours, the EN_HIZ (REG00[7]) is set to signal the buck converterstops and the system load is supplied by the battery. The EN_HIZ bit can be cleared to restart the buckconverter.
之所以重新配置就生效，很可能就是因为重写REG00寄存器时，重新给EN_HIZ位为0；重新启动了升压转换器；现在问题已解决！
Zhengxing Li：
回复 hugang Ding1:
对于BQ24195这个料，一个忠告就是，各种状态切换或初始化时，最好都首先对HIZ进行置位，确保芯片得到确定的状态。
