Charging voltage problem

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魏文彬
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Last seen: 1 day 20 hours ago
Joined: 2019-04-10 03:51
Charging voltage problem

I have a very serious problem。

When I charge a lithium battery with almost no power (about 3v), I plug in the USB and measure the voltage across the battery to 4v. The charging voltage is 1v than the current voltage of the battery。

I use "ble_sps_peripheral" project  in DA14682 platform.

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#define DEBUG_SOC                                                                                                   //DEBUG(hold 2000 . ram size)
#define dg_configBATTERY_TYPE                           (BATTERY_TYPE_CUSTOM)
#define dg_configBATTERY_CHARGE_VOLTAGE                 0X0A                              //4.2v
#define dg_configBATTERY_TYPE_CUSTOM_ADC_VOLTAGE        (3410)                  //y[ADC units]=(4095*Vbat[Volts])/5  
#define dg_configPRECHARGING_THRESHOLD                  (2457)                           //3.00V
#define dg_configCHARGING_THRESHOLD                     (2498)                              //3.05v
#define dg_configBATTERY_LOW_LEVEL                      (1000)                                  // Turn off this feature first
#define dg_configBATTERY_CHARGE_CURRENT            6                                        //210mA
#define dg_configBATTERY_PRECHARGE_CURRENT      20                                     //2.1mA
#define dg_configBATTERY_CHARGE_NTC                     1                                       //disable
#define dg_configPRECHARGING_TIMEOUT                (30 * 60 * 100)
#define dg_configUSE_SOC                                            1                                        // Charge function is enabled
#define dg_configUSE_USB_CHARGER                           1                                       //use usb charger
#define dg_configUSE_USB                                             1
#define dg_configALLOW_CHARGING_NOT_ENUM        1
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thanks

Device: 
PM_Dialog
Online
Last seen: 22 sec ago
Staff
Joined: 2018-02-08 11:03
Hi There,

Hi There,

The 4V that you are measuring is the expected value due to the dg_configBATTERY_CHARGE_VOLTAGE. Since you are using a lithium battery the 0x0A is the recommended value of this macro. Please check the  CHARGER_CTRL1_REG[CHARGE_LEVEL] for the table 559 of the DA14682 datasheet. You are measuring the Constant Voltage Levels.

Thanks, PM_Dialog

魏文彬
Offline
Last seen: 1 day 20 hours ago
Joined: 2019-04-10 03:51
I set dg_configBATTERY_CHARGE

I set dg_configBATTERY_CHARGE_VOLTAGE = 0x0A

And My lithium battery has a charging voltage of 4.2v and a minimum discharge voltage of 2.7v.

BUT When my lithium battery is about 3v, the charging voltage of the lithium battery is measured as 4v / 120ma.

In the initial stage of charging should be constant current charging,the voltage should be a little bigger than 3v ???? right?

There is no api function for configuring constant voltage/constant current charging in sdk

Below is my configuration:

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#define DEBUG_SOC           
#define dg_configBATTERY_TYPE                                       (BATTERY_TYPE_CUSTOM)
#define dg_configBATTERY_CHARGE_VOLTAGE                 0X0A  
#define dg_configBATTERY_TYPE_CUSTOM_ADC_VOLTAGE        (3410)
#define dg_configPRECHARGING_THRESHOLD                  (2457)         
#define dg_configCHARGING_THRESHOLD                        (2498)                  
#define dg_configBATTERY_CHARGE_CURRENT                 6           
#define dg_configBATTERY_PRECHARGE_CURRENT              20    
#define dg_configBATTERY_CHARGE_NTC                     1       
#define dg_configPRECHARGING_TIMEOUT                    (30 * 60 * 100)
#define dg_configUSE_SOC                                1      
#define dg_configUSE_USB_CHARGER                1   
#define dg_configUSE_USB                        1
#define dg_configALLOW_CHARGING_NOT_ENUM        1

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