BQ24002PWP Single Li-ion battery charging circuits component are not available in my city.

You can also try to achieve those values by putting pair of resistors for each value, or replacing one of the voltaje adjust resistors by a trimpot

Hi Sir,

 Thanks for all of you, and Sorry for late reply from my side. actually  we have kept this work pending  because we worked on  other project.

Now, we came back to this project again. we got some approximate value component from market & place according to circuit for testing purpose, such as

we place 0.1 ohm => 0.1 ohm/3 watt

                 18.7K      => 18K/1206 package

                 95.3k      => 100K/1206 Package

                       After such arrangement the circuit was not working. because we get 1.99V at APG/THM. Then we have replace 18K to 82K,( we get 0.99V at APG/THM) now circuit working properly if battery voltage is above than 3.59 v. but if battery voltage is below 3.59 V then circuit is not working properly, means if i am trying to charge fully discharge battery, the circuit will charge the battery for 3-4 minute then circuit stop working & charging circuit was 0 mA (at that time battery voltage was 3.59v ). after that i have removed battery  & insert it again, then the circuit working properly till battery full charge. 

    The circuit working like

1.  if battery voltage above 3.6 v,  the circuit charge battery properly.

2. STAT1 LED glows, when battery voltage is below 90%.

3. STAT2 LED glows, when battery voltage is above 90%.

         But circuit is not working properly as i mentioned above. Please help me where i am going wrong.

 Please find the attachment for circuit diagram which i have design,

Thanks for your reply.

I have some query regarding the circuit, please guide me,

1. why the circuit was not working when i used voltage divider resistor RT1=18K & RT2=100K

2. what is the use of  resistor  R1=51.1 kΩ  &  R2=215 kΩ as shown in the User Guide.

Thanks 

Kashinath

Always refer to the block diagram to understand what is going on.

The divider is connected to a window input and if that voltage is not within the specified voltage window, it does not charge, so the first step is to place a scope probe on the signal and see if the DC and AC portion of the waveform are within the specified range.

The divider goes to J2 which allows a voltage from the thermistor or input to be monitored by the window comparator.  Key point is that what ever voltage applied, it has to be withing the specified range.

Hi sir,

Please tell me how to calculate the value of RT2 from below equation,

RT2= VB RH RC[(1/VC) - (1/VH)] / RH(VB/VH-1) - RC(VB/VC-1)

I have search the datasheet but still i am not able to find the value of terms used in the equation, i  got only 2 terms value from datasheet

VH = 1.498  ( VP2 or the upper APG trip threshold)
VC = 0.558 ( VP2 or the lower APG trip threshold)

What  is the value of below terms used in the equation?

1. what is the value of VB=?,

2. what is the value of RH=?,

3 What is the value of RC=?

  I am using NOKIA BL-5C-H (3.7V/1050mAH) model battery for charging purpose.

Thanks,

Kashinath

Please someone help me.

They are defined on page 15 of the data sheet next to the equation....VB=Divider bias=Vcr; Rh=thermast value at the temperature you consider hot; Rc=thermast value at the temperature you consider cold.

Thanks for your suggestion, the problem seems to be solved now after connecting 10pf capacitor between TMR and CR.

Now i have another query, i have connected load at the output, and i start the charging of fully discharge battery, then circuit will charge the battery for some period & then STAT1 LED start blinking. it seems to be FAULT condition.

Please suggest me on the same.

Thanks for your suggestion, but i wan't to know the value of these variables. 

If i am not wrong, then VB=Vcr-2.85V

how i get the value of RH & RC.

Refer to the manufacturer's data sheet of the thermistor.  They should have resistor values over a temperature range.

For a 103AT type of thermistor, at 0C: ~28k and 45C: ~4.6k....I am doing this from memory so be sure to check

Please give suggestion for solving load Issue during charging(Battery voltage <3V) . Please refer my above post for detail explanation. 

Thanks in advances.

The load is not defined so it is hard to say exactly what is happening.

In general, refer to the charge profile for precharge and fast charge, one can't load the output more than the programmed charge current otherwise the battery discharges.

In precharge, there is not much excess current so any load at all might keep the battery voltage from getting to the LOWV threshold and enter fast charge before a precharge fault condition occurs.

The load requirement is,

1. 3.3V for micro-controller  operation.

2. 4.2V - 3.2V for GSM module operation

3. The total load current is 90mA.

Your circuit should work.

Best to order an EVM and see how it works.

Thanks for your reply, but circuit is not working.

I have tested the circuit & found that, the load take 90mA current for first few second, after that it takes 400mA current for 3-4 Second & then it takes 90mA constant current.

Please help me.

Are you using a real battery or a battery simulator.

Please post waveforms of each pin of the IC so I can see what is going on.