PMU Forum - Recent Threads

nRESET timing in TPS65217A

Vincenzo Pizzolante — Mon, 22 Apr 2013 13:13:39 GMT

hello

on TPS65217A datasheet there is indicated to keep nRESET low for 1sec to reset the device...

a customer wish to know whether is possible to shorter this time and/or why it needs such a long time...

tks a lot in advance

Vincenzo

PMU to power up a ARM AM3359 + TMS320VC5509 + ADS1274

Andre Luiz — Mon, 20 May 2013 20:34:46 GMT

Hi,

I need a PMIC that can suply voltages for a ARM AM3359, a DSP 5509 and a ADS1274 converter in the same board. Here's the voltages:

ADS1274: 5v, 3v3, 1v8 and 2v1

DSP 5509: 1v6, 3v3

AM3359: 1v8, 3v3

Is there a single IC that satisfy my project?

tps65217B PMIC SYS pin output problem

ye luo — Sat, 18 May 2013 08:35:08 GMT

Hi,

We are using tps65217B PMIC for powering a custom board based on AM3352 .

The design is not battery powered. The problem is after connecting 5V to the AC, PMIC is starting, The SYS pin output correctly, and VLDO1 output is 1.8V, DCDC1 output is 1.8V, DCDC2 output is 1.1V, DCDC3 output is 1.1V,

But after 2 s the PMIC goes to fault state, SYS pin output and all power rails turned off.

Then repeatly after 2s is ok, after 2s is wrong................

The Attached is Schematic.

pls help me check.

thanks.

Exploiting LP3913 VIN1 input

Riccardo Brama — Thu, 12 Jan 2012 12:23:05 GMT

Dear Community,

I'm wondering if it is possible to use LP3913 VIN1 input voltage (the one feeding LDO1 and LDO2) connecting it to one of LP3913 Buck outputs such as BUCK1.

This would prove quite useful in one of my designs. I'm planning to test such a "trick" in next few weeks, but if you have some suggestions, they are more than welcome!

Sincerely,
R.

TPS650250 Powered by Buck Converter

Matt Romney — Thu, 16 May 2013 17:59:22 GMT

In researching the PMIC's recommended for the AM335x MPU, the datasheet for the TPS650250 states that it is intended for use in Li-Ion powered systems. Is there any reason that it could not be connected directly to a buck converter with an output of 5VDC? The other two recommended PMIC's offer more features, at a higher cost, than is needed in our system so the TPS650250 is preferred. The only other concern I have would be, since the TPS650250 does not have a RTC, in case of power failure, would a cell battery be sufficient to keep the RTC on the AM335x running for an extended length of time.

Thanks for the help.

Beagle Bone + TPS65217 query

rajesh ravnikar — Thu, 16 May 2013 13:56:41 GMT

Hi TI ,

I have a few queries on TPS65217.

1.In page 20 of TPS65217 data manual , it is said that LDO_PGOOD output goes high when LDO1 and/or LDO2 are enabled . This is creating a lot of confusion .

Is it and or or??

2. When the TPS65217 is in sleep mode only LDO1 will be on . In that case does LDO_PGOOD be high?

3. To wake it up from the sleep mode if we press the PWR button does the PMIC toggle the WAKE_UP signal and the processor in turn has to come and enable PMIC_PWR_EN signal to enter active state . Is my understanding correct ?

4.Can the device be powered off by pressing the power button of PMIC TPS65217 ? Looking at the datasheet i understand that feature is not possible.

Thanks in Advance.

Best Regards,

Rajesh N

TPS65217A PMIC IC doubt

prabha krishna — Wed, 15 May 2013 11:39:15 GMT

Dear Sir/Madam,

In our Project we are using TPS65217A PMIC IC. We are giving External power supply i.e 5V then this 5V is given to TPS65217 IC 12th Pin and see the SYS o/p pin no 7 and 8 but we are not getting 5V i.e 0.269V is coming. I saw the TPS65217 datasheet but i did not get anything. can you please give me the your valuable feedback.

Thanks&regards,

GKP

How to power on tps65910 by the RTC alarm(INT1)?

love-linux — Tue, 14 May 2013 14:39:21 GMT

Our projects have been used the PWRON button to control power, but we also want to power on PMIC by RTC alarm, how to deal with it,in circuit and software?

TPS65051 can support Freescale IMX258?

sky Huang — Tue, 14 May 2013 08:35:11 GMT

Dears,

I have found out TPS65051 can support Freescale IMX25.

Let me confirm TPS65051 also can support Freescale IMX258, right?

Sky

PMIC Power Consumption for light load

Jayden Park — Tue, 14 May 2013 03:02:43 GMT

Hi~

Out customer use TPS65270. Our customer have power consumption spec for light load.

Vin : 12V, Vout1 : 3.3V, Vout2 : 1.5V

Our customer search part to meet follow condition : Light Load : 10mA => Efficiency 80%

Please recommend part and another solution.

tps65381-q1 multi rail power supply

Madhu Vatte — Tue, 07 May 2013 13:10:35 GMT

Hello,

Is there a similar part like tps65381-q1 with load dump protection?

Thanks,

Madhu

tps65217B PMIC start up problem

Mehdi_ — Wed, 08 May 2013 08:12:38 GMT

Hi,

We are using tps65217B PMIC for powering a custom board based on AM3359 (We used Beaglebone as a reference ). The design is not battery powered. The problem is after connecting 5V to the AC, PMIC is starting, the LDO_PGOOD gets high(VIO is 3.3V) and VLDO1 output is 1.8V, but after ~1 s the PMIC goes to fault state and all power rails turned off. We have an LED connected to the VLDO2 to check the PMIC state, it just turns on for a second and then turns off. We disconnected all the loads on rails to ensure that it is not a shorted output. We evaluate the OVT condition as well with increasing the voltage to 6 volt which the PMIC responded correctly. We tried to disconnect the AM3359 from the PMIC (VRTC on VLDO1 and other power rails ) and setting PWR_EN to high using VLDO1(1.8v) manually but same thing happened and the PMIC turned off after one second operation and all the power rails, LDO_PGOOD and PGOOD went down. Could you please give me some tips to solve the problem?

Tps65090 question

Eric Ho — Mon, 06 May 2013 16:26:13 GMT

Dear All,

I have some Tps65090 question,

a. If customer wanna use 3S battery, how do i design the FBC pin resistor??

b. For TS pin design, could I combine two to one to sense?

c. For the input R-sense & output R-sense, the EVM design is 10mohm, if customer wanna change to 15mohm or 20mohm, do we need to change software code or not?

Thank you

TPS65251-Q1 Filure Rate of internal each functional blocks

Toshio Ushikubo — Wed, 24 Apr 2013 13:53:08 GMT

(Please visit the site to view this file)

Hello,

Customer requests me the Failure Rate(FIT) about each internal functional blocks.

I have already submitted FIT of TPS65251-Q1.

I need the Area percentage of internal function blocks to calculate the FIT of each blocks.

Regarding TPS65381-Q1

hideyuki sakai — Mon, 22 Apr 2013 03:54:39 GMT

Dear, Sir.

TPS65381 includes Diagnostic and Watch-dog(WD) fuction. I would like to make sure the method to check all regulator output in an early phase of system develpment because MCU is not available yet.

1. At first, BATP and VBAT_SAFING with additional capaciors must be connected to proper input voltage supply? 2. Is it needed to be disable WD fuction? 3. All regulator output check is avaliable under DIAGNOSTIC or ACTIVE modes? 4. Is there any special condition to check all regulator output?

Best Regards,

TPS650250 efficiency of LDO's

Perry Frogge — Thu, 11 Apr 2013 19:53:52 GMT

I can't find anywhere, the efficiency of the LDO converters. My board design is sensitive to even 1mA of wasted current. I have implemented the circuit given below, not using TPS650250 LDO's because I cannot quantify their efficiency. I could save BOM, board space etc. if I knew the LDO's of the 650250 would be close to the 60% I get with the TPS73101.

I have all 3 of the switching regulators in use, so i cannot use one of them.

thanks

I have implemented a TPS73101 with 1.8V in and 1.2V out, at 10mA max, Webbench says it is 60% efficient at 8mA. So my

TPS65217B Battery charging

USHA M — Sat, 20 Apr 2013 12:24:41 GMT

Hi,

I am using TPS65217B as PMIC for AM3352 processor. The design is a battery operated device.

I would like to know the details about the time required for charging the battery with 1200mAh capacity. Both DC and USB charging is used.

The system supports a load of 1A. Also, please provide details about the time required for quick charging.

Thanks,

Usha

TPS65217B WLED driver circiut

USHA M — Wed, 24 Apr 2013 07:42:35 GMT

Hi,

I want to use the internal WLED driver of PMIC TPS65217B . WLED Boost regulator is capable of providing upto 39V,25mA each LED string(Two strings can be used)

I am using a 3.5" LCD which requires 19.8V backlight voltage with 20mA of current . ISET pins are set to required current using resistors. (18uH inductor is used for switching)

Is that boost regulator a current mode PWM regulator that will take care of backlight voltage required by LCD depending on current set by resistor ??

Or is it neceesary to set the backlight voltage externnally ?? If yes how to do this as feedback (FB_WLED) pin voltage need to be set is not mentioned in datasheet??

Immediate reply is appreciated.

Thanks,

Usha

TPS65258EVM

Rod Lopez — Wed, 24 Apr 2013 17:43:16 GMT

Technical Information!!! TPS65258 EVM

How can I setup the USB Switcher on the board? I mean ...can I feed the Vin of the USB switcher with the out of one of the Buck converters ? It will be enough the 3.3 V or I will need an external DC source of 5V? How can I enable the USB switcher with AN external drive signals?

Thanks...

TPS65217C with NiMH Battery

Charles Eidsness — Tue, 16 Apr 2013 16:03:19 GMT

Hi,

I would like to use the TPS65217C with 4 NiMH Cells and an external charger and use the Power Path control in the TPS65217C if I can.

I'm thinking that if I connect the NiMH Cells to the BAT pin and leave the Temp Sense pin floating so the internal charger never turns on this could maybe work. The operating voltage for the 4 NiMH cells is 3.5V to 5.5V and the charging voltage would be up to 6.4V. The 6.4V falls out of the operating range of the BAT pin but within the absolute maximum rating. The AC will always be plugged in while charging so the BAT pin technically won't be operating.

Is this okay or will I have to include my own Power Path switch that can handle the higher voltage?

Thanks,

Charles

About TPS65023　LOWBAT_SNS pin and PWRFAIL_SNS pin

masa0301 — Thu, 18 Apr 2013 14:55:52 GMT

My coustomer want to no use LOWBAT_SNS pin and PWRFAIL_SNS pin at TPS65023.

Can I possible no use LOWBAT_SNS pin and PWRFAIL_SNS pin?

If I can no use these pin,could you tell me where must be connect.

Best regards

masa0301

TPS65381-Q1 Component Values - Reverse Polarity

Rustin Schroeder — Tue, 16 Apr 2013 16:30:40 GMT

Does TI have a recommendation for component values for the TPS65381-Q1 reverse polarity circuitry as shown in the figure below (specifically resistor / capacitor):

TPS650250 EN to Output timing

PAN-M — Mon, 08 Apr 2013 09:27:35 GMT

Please teach me the time from EN active to voltage output.

Figure 17 in the datasheet is not written time division and each timing is different.

Regards,

PAN-M

TPS650250

David Zlater — Wed, 10 Apr 2013 09:23:15 GMT

In the TPS650250 datasheet 3,3uH is "required for output voltages >2.8V" but this is a bit confusing since w.c. ripple current is at VOUT = VIN/2, see analysis below. It is also a bit confusing that SLVU731A has a 3,3uH inductor for the 1,1V supply without explanation. In the two example diagrams in the datasheet, one has 2,2uH for all 3 DCDCs, and one has 3,3uh for the 3,3V reg.

If ripple current is the issue then there is a double fault in the texts mentioned. It should read: "Larger inductance might be a good idea the closer VOUT is to VIN/2".

Analysis: I_RIPPLE = VOUT*(1-VOUT/VIN)/f/L; dI_RIPPLE/dVOUT = (1-2*VOUT/VIN)/f/L; Maximum I_RIPPLE is when dI_RIPPLE/dVOUT = 0 i e VOUT = VIN/2. In our case we have VIN = 5V so w.c. in for VOUT = 2,5V (and max allowed VIn is 6V so it won't get much higher in any application).

(Note: This is a copy of a post I put in the analog forum. I was told to put it in Power Management.)

Edit: Added "= 0" after "dI_RIPPLE/dVOUT"

About TPS65023 Loop Gain ,Phase marjin

masa0301 — Thu, 11 Apr 2013 10:03:16 GMT

Could you tell me how to measure Loop and gain margin at TPS65023?

My customer no use FB resistance. Use default output voltage.

If can measure, please let me know pace to measure

Best Regards

PMU Forum - Recent Threads

nRESET timing in TPS65217A

PMU to power up a ARM AM3359 + TMS320VC5509 + ADS1274

tps65217B PMIC SYS pin output problem

Exploiting LP3913 VIN1 input

TPS650250 Powered by Buck Converter

Beagle Bone + TPS65217 query

TPS65217A PMIC IC doubt

How to power on tps65910 by the RTC alarm(INT1)?

TPS65051 can support Freescale IMX258?

PMIC Power Consumption for light load

tps65381-q1 multi rail power supply

tps65217B PMIC start up problem

Tps65090 question

TPS65251-Q1 Filure Rate of internal each functional blocks

Regarding TPS65381-Q1

TPS650250 efficiency of LDO's

TPS65217B Battery charging

TPS65217B WLED driver circiut

TPS65258EVM

TPS65217C with NiMH Battery

About TPS65023 LOWBAT_SNS pin and PWRFAIL_SNS pin

TPS65381-Q1 Component Values - Reverse Polarity

TPS650250 EN to Output timing

TPS650250

About TPS65023 Loop Gain ,Phase marjin

About TPS65023　LOWBAT_SNS pin and PWRFAIL_SNS pin