BQ24773: BQ24773 Standalone Testing

Hey Rahul,

1. The BQ24773 charging portion will not function without programming the device.

2. Yes, you need to configure the BQ24773 in order to charger. However, the system rail will be regulated as long as a valid input source is present.

3. We do not have reference to work with any particular controller or host. There is a third-party firmware written for the charger here: https://chromium.googlesource.com/chromiumos/platform/ec/+/master/driver/charger. However, please note this code is third-party and not supported or created by TI, so perform your own due diligence when coding the firmware.

For sake of consistency Rahul, I will loop in the other threads you have posted here, as the issue is getting a little confused between your various posts. I will close the other threads and respond to this thread.

https://e2e.ti.com/support/power-management/f/196/t/844044

https://e2e.ti.com/support/power-management/f/196/t/844633

1. Please refer to my comment no.8 in the previous threads:

8. I think we need to look at a startup waveform showing the ACDRV voltage and CMSRC voltage, the VCC voltage, and the SRN voltage. You should overlap the ACDRV voltage and the CMSRC voltage ground point. I would also capture the ACDET voltage with 500mV/div at least to capture the change in the input.

This waveform will help us get closer to determining why the ACFETs are not turning on and why the ACOK status is still low.

Regards,

Joel H 

Hello Joel,

                 I try to write code on Arduino for BQ24773 Configuration, but we facing some issues 

1. Fail to read written data on register, reading register written data by using logic analyzer  

2. Can you please send right sequence of register and value of registers for configuration

3.MaxCharge voltage , ChargeCurrent and InputCurrent not going to set as per the requirement, there is any dependent register of this registers ..?  

4. Setting of other register affected on this register..?

5. what is the right register configuration of 5V/2.5A register to get VSYS= 5V/1A on charge current 1A ..?

Thanks and regards, 
Rahul Surawase 

Hello Joel, 

                 We configure the system by using Arduino and cross verify register data by reading the registers 

Check configuration setting 
      We have same issue which observe before, no change in system voltage REGN shows 0.7volts and ACDRV voltage not going to change still 0v or  <100mV

  There is anything wrong ..? we can't figure out where is the issue, Please verify above mention schematic and configuration setting 

Thanks and Regard,
Rahul Surawase

Hey Rahul,

Again, I am still looking for a waveform as mentioned previously.

Can you please provide this to move forward?

Regards,

Joel H

Hello Joel,
                  TAke look ACDR waveform which observe on config setting as per mention in config image, there is no any change in REGEN and ACFET & RBFET 

1.Input adapter= 5.2V/2.5A

2.Battery(Lithium Ion) = 2200mA (3.7 O/P)

After configuration by using Config1 setting,

1.Vsys= 3.84V
2.ACDET=2.6V
3.ACOK=10mV
4.PROCHOT=3.2V
5.HIDRV= 3.5V
6.LODRV=0.7V
7.REGN=0.7V
8.VCC=4.8V 
9.ACDRV=400mV
                              Observe voltage ..!

Thanks and regards, 
RAhul Surawase

Hello Joel,

                      As per your requirements we capture startup waveform, 

8. I think we need to look at a startup waveform showing the ACDRV voltage and CMSRC voltage, the VCC voltage, and the SRN voltage. You should overlap the ACDRV voltage and the CMSRC voltage ground point. I would also capture the ACDET voltage with 500mV/div at least to capture the change in the input.

This waveform will help us get closer to determining why the ACFETs are not turning on and why the ACOK status is still low.

                  Sorry for the delay...!

Thanks and Regards, 
RAhul Surawase 

Hello Joel, 
                  What about the ACOK and REGN LDO ..?

What is the ACOK status when Input adapter is connected, It's need to be High right ..? but its not going change the state its always Low shows 10mV

REGN LDO also shows 0.7V only, expected REGN voltage is 4.4 right ..? what is reason of that behavior ..?

Also satisfy all this below mention conditions 

• V(UVLO) < V(VCC) < V(ACOVP)

• V(ACDET) > 2.4 V

• V(VCC) – V(SRN) > V(VCC_SRN_RISE)

And to confirm, 1. ACDET here is always above 2.4V, correct?

ACDET set to 2.56V by Using R6 100K & R9 100K when Vin is 5.2V

2. Is there a load on the system side when the adapter plugs in?

No, there is no any load on the system side but we also check with load by using 1W DC load  there is no any change found on System performance 

3. You also mentioned you tried with a 12V power supply, and same result, correct?

YES, not found any difference with 12 V adapter 

Also check with C2 10uF and C3 10uF capacitor inserted between HSFET and RAC resistor no change Input waveform of ACDRV and CMSRC signal 

                               waiting for your valuable response   ...

Thanks and Regards,
Rahul Surawase

Hey Rahul,

A few comments:

ACOK is based on the ACDET voltage, the VCC voltage being above the UVLO threshold, and VCC being above the battery voltage. 

What is not clear to me looking at your ACDRV-CMSRC voltage is the spike in the CMSRC voltage. 

Let's try a couple of other things:

1) Short across the R1 resistor and retry your test. I am trying to see if this is a product of an inrush current spike that is hitting some over-current condition and disabling the input FETs. If you short across RAC, the differential voltage will be small for any amount of current.

2) Just to confirm everything is connected correctly, short across Q1 (from D1 to D2), and remove R7 and R8, and tie the ACDRV and CMSRC pins together with a 500-kOhm resistor. This should confirm whether the rest of the charger is operating correctly.

Regards,

Joel H