about BQ500212A

Hi Takao,

you can refer to Bill John's excellent presentation about the sleep and snooze functions at the link below

 http://e2e.ti.com/cfs-file.ashx/__key/communityserver-discussions-components-files/693/3377.bqTESLA-TX-Sleep-Mode-_2D002D00_-212A.pdf

Hello Takao 

Q1, What is the function of SNOOZE_CHG and SNOOZE_CAP?

Q2, BQ500212A's datasheet say 'SLEEP pin connected to 5s interval circuit' and 'SNOOZE pin connected 500ms interval circuit'.

 A1 / A2 --- See forum post “FAQ-bqTESLA TX Sleep Mode -- RC Time Constant Based”

http://e2e.ti.com/support/power_management/wireless_power/f/693/t/372430.aspx

This is the PDF that Mahmoud pointed out.

If you have additional questions on this do not hesitate to repost the question.

Mahmoud –thanks for the help

 

Q3, Can we use transistor in place of CSD97376Q4M?

  If this is possible, should we set 'Base:PWM signal / Collector:VIN / Emitter:Tx Coil' ??

A3----The CSD97376 is an integrated power stage device with driver and two MOSFETS.  It can be replaced with an external driver and two external MOSFETs.  See the bq500211 EVM, this design uses external driver and mosfets, can be used with the bq500212A also.

http://www.ti.com/lit/ug/slvu536a/slvu536a.pdf

Q4, How can we use JTAG and DATA signal?
  Datasheet say these pin are used for debug. But, what can we do in the concrete?

A4—the JTAG is for factory use only.  The I2C interface will be used for FOD set up and debug. 

Bill and Mahmoud, thank you for your help!!

Dear Bill,

I have some additional questions. Please teach me.

[about the PDF]

Question 1 ---Can we change Snooze Time and Sleep Time by changing values of resister and capacitor?

Question 2 ---What is the mean and function of 'First Power On Speed Up ckt'? (page.4)

                      If there is not this circuit, what is going to happen?

Question 3 ---I think that BQ checks Snooze_Cap and go to Snooze mode if Snooze_Chg is sent pulse.

                      So, BQ continues to run if Rx need to keep power on and Snooze_Chg is not sent pulse.

                      Is this wrong?

Question 4 ---In page.5, Snooze function is described. But Sleep function is not described.

                      Is Sleep function similar to Snooze function?

                      Please teach me about the detail of Sleep function?

[about A4]

Question 4 ---In your A4, you mentioned 'factory use only'.

                      Does the 'factory use only' mean that no customer can use these pin(JTAG and I2C)?

Best regards,

Question 1 ---Can we change Snooze Time and Sleep Time by changing values of resister and capacitor?---BJ--Yes

Question 2 ---What is the mean and function of 'First Power On Speed Up ckt'? (page.4)

                      If there is not this circuit, what is going to happen?----BJ—Used to detect the first time power is applied, some LED modes use this feature.  If not used pull up to 3.3V

Question 3 ---I think that BQ checks Snooze_Cap and go to Snooze mode if Snooze_Chg is sent pulse.

                      So, BQ continues to run if Rx need to keep power on and Snooze_Chg is not sent pulse.

                      Is this wrong?----BJ--The bq will send a pulse out of Snooze_Chg, cap is charged and bq turns off.  When bq wakes up it checks the Snooze_Cap, if it is high the bq knows it has been in Snooze not Sleep.

Question 4 ---In page.5, Snooze function is described. But Sleep function is not described.

                      Is Sleep function similar to Snooze function?----BJ—Yes, same but of 5 sec not 500mS.

                      Please teach me about the detail of Sleep function?----BJ—Longer off time that is used for charge complete to reduce standby power.

[about A4]

Question 4 ---In your A4, you mentioned 'factory use only'.

                      Does the 'factory use only' mean that no customer can use these pin(JTAG and I2C)?-----BJ—JTAG yes, I2C—can be used for FOD calibration and set up.

Thank you for your answers.

Additionally, I would like you to teach me more about your answers.

 

Question 1 --- I would like to know how to select values of capacitor and resistor for changing Snooze time and Sleep time.

Question 2 --- You said that 'If not used pull up to 3.3V'. Is this about 44pin(LED_MODE)?

                       I would like to know if we can design circuit without 'First Power On Speed Up ckt'.

Question 3 --- I think that ''The bq will not send a pulse out of Snooze_Chg, cap is not charged and bq turns off.  When bq wakes up it checks the Snooze_Cap, if it is low the bq knows it has been in Sleep not Snooze''. Is this correct?

                       I would like to know the mechanism of Sleep mode for Standby.

Question 4 --- About I2C. In fact, is there the situation of customer using this pin for FOD calibration and set up?

                       What is the difference from pin 15?

 

Best regards,

Dear Bill,

Please teach me about the PDF at forum post “FAQ-bqTESLA TX Sleep Mode -- RC Time Constant Based”.

http://e2e.ti.com/support/power_management/wireless_power/f/693/t/372430.aspx

Q1,

According to this PDF, BQ500212A will send a ping when it wakes up from Snooze mode.

Is this device will send a ping in other situation?

I wonder if this device will work well when we remove Sleep and Snooze circuit.

If this device only send a ping after waking up from Sleep/Snooze mode, can not  this device communicate with Rx without Sleep/Snooze circuit?

Q2,

In flow chart at page 5, you said 'BQ wakes up checks Snooze_CAP To determent mode'.

What is the purpose of looking at the voltage of Snooze_Cap?

What is the determent mode?

Best regards,

A1,

When the device wakes up it will send a ping to check for the RX for both Sleep & Snooze.

Device can operated without external Sleep and Snooze circuit by using LED mode 2.

In LED mode 2 power will be applied to the bq500212A all the time and standby power will be higher.

 

A2.

LED is treated different in when waking up from Sleep vs waking up from Snooze.

Dear Bill,

Thank you for your reply.

And I would like to make sure following.

■About A1

We can use this device without external Sleep and Snooze circuit by using LED mode 2.

But, why LED mode 2 only?

This device can communicate with Rx without external Sleep and Snooze circuit, is this right?

■About A2

I could understand that the purpose of checking Snooze_Cap is to distinguish between Sleep and Snooze.

But, where is this mentioned about LED?

Best regards,

But, why LED mode 2 only?---In other modes the device is expecting the external circuit to control timing. External ckt is required or unit will not operate correctly.
This device can communicate with Rx without external Sleep and Snooze circuit, is this right?---No, without external timing ckt the device will not turn on and operate correctly.

Dear Bill,

Thank you for your reply.

I could understand the purpose of checking Snooze_Cap.

But, what is the 'determent mode'?

Best regards,

Q2,

In flow chart at page 5, you said 'BQ wakes up checks Snooze_CAP To determent mode'.

What is the purpose of looking at the voltage of Snooze_Cap?

What is the determent mode?

---BJ-The voltage on Snooze_CAP is used to decide if the device is waking up from a short Snooze or longer Sleep mode.  Voltage on the circuit will decrease at a known rate while the unit is off.  Below 1.25V the bq500212A will declare that it has been in a sleep mode.  Above 1.25V the bq500212A will declare that it has been in a snooze mode.

Dear Bill,

Thank you for your reply.
I have understood this function.

Additionally, I would like to know about fault function.
There is 'FAULT' at data sheet Table 1.

Could you explain what is fault event specifically?
For example, over current, over voltage and over temperature?

Best regards,

LED Modes, Table 1 provides several options for a “Fault”. The most basic behavior would be the LED2, Red turning on. But other options are blinking of Red or both Red and Green blinking.
A fault is any of the End Power Transfer (EPT) conditions listed in table under “Fault Handling and Indication”. During a fault power transfer has stopped and the TX is in a low power mode with no power going to the RX.

【!!!URGENT!!!】*please reply quickly.

Dear Bill,

Thank you for your reply.

And, I have confused about external timing ckt (Snooze/Sleep) yet.

So, please teach me more information below.

You said that 'without external timing ckt the device will not turn on and operate correctly'.

Is this just as valid for LED mode 2 ? 

On my board, without external timing ckt at LED mode 2, BQ500212A could turn on, communicate with BQ51013B, and transfer power.

Could you explain the reason concretely why you said that BQ500212A will not operate correctly?

At least, the circuit written in your document page.4 (First Power On Speed UP ckt / Sleep ckt 4sec long off time / Snooze ckt 400 ms short off time) simply make the timing for 3.3V supply(U5).
So I think that the timing ckt is not necessary to charge Rx at LED mode 2 (the case of 3.3V supply being active all of the time).

Best regards,

7181.bqTESLA TX Sleep Mode -- 212A.pdf

See FAQ section of forum, I have updated the bqTESLA Sleep Mode -- RC Time Constant based.
LED Mode 2 -- Timing control is internal, external RC not required
LED Mode 9 -- Sleep (5 sec) timing control is internal, external SLEEP RC not required.
For all other LED Modes external RC circuit for Sleep and Snooze is required of correct operation of device

Dear Bill,

Thank you for your update.

In the result, is it right that Tx can communicate with Rx and transfer power with no external timing ckt at LED Mode 2 with no hitch?

Best regards,

Hi Takao Yamamoto
In regards to your question:
" is it right that Tx can communicate with Rx and transfer power with no external timing ckt at (in) LED Mode 2 with no hitch?"---YES