Part Number:TPS799
Hello,
The output is volatge is rated up to 6.5V, the discharge resistor is 400Ohms.
In an application with high output capacitance, without load, the capacitor's energy will dissipate in the discharge resistor
Is there a power dissipation limitation for the output discharge resistor?
Thank you
Part Number:BQ40Z80
I was wondering what the schedule is for release of this part? I See there are EVMs in distribution, but the part doesn't show up. At this point, even samples would be helpful.
Part Number:UCC28780
Question: everybody is suggesting the use of general MOSFET drivers to adapt to GaN by adjusting to 5V drive levels.
So, why can I not use UCC24610 for driving the synchronous switch which we choose to be EPC2034 instead of a MOSFET will extreme parasitcs? Other than that the voltage controlled enhancement mode switches have "similar" V-I characteristics notwithstanding different physics of the devices. Their Vgs- I transfer characteristics are also "similar".
In fact, other than super high slew rate of switching, one is able to replace all topologies from traditional MOSFETs to GaN, yes?
In the Active Clamp based controller UCC28780, is there any reason this wont apply?- i.e., replacing the suggested MOSFET to GaN?
just trying to be "innovative" here!
I have already suggested using UCC24612 with 5V by following what the datasheet says: that all internal circuitry is run from 5V generated by internal LDO & ouptut at REG pin. So if one leaves VDD pin unsed & connects 5V regulated by an LDO to drive a GaN?
If UCC24610 already does it, yes, of course, we would use it- saves many tiny components for us.
r
Part Number:BQ27220
Hi,
My client has a battery powered device that uses BQ27220. I will get a testing board next week and I am trying to get familiar with the way that BQ27220 works in order to be able to integrate it into software. The problem is that I don't understand exactly what are the minumum parameters that I have to set in order to get it working. The used battery will be https://www.ultralifecorporation.com/ECommerce/product/ubp002/li-ion-cell-053450-pcm.
Regards,
Gabriel
Part Number:BQ24171
Hi Support team
My customer has the following question, I can send scope shot and schematic
The device uses a 3S1P battery pack and uses the TI BQ24171RGYR battery charger, which is the same circuit as the previous gen device.
From our testing, we have noticed that in some cases, the battery charger is not charging the battery. It is not easy to reproduce this issue, but it occurs when the battery is discharged to some level such as 50% or 70%, and then external power (EXT_PWR) is plugged in. In this state, we see the following:
It appears the STAT pin is indicating some sort of fault, but I am not sure how to identify the fault type. The battery voltage in this case is around 10V. It appears that periodically, the charger is outputting voltage and the BATT_POS jumps up to 12.48V. This seems abnormal to me since the battery voltage should not change so suddenly. Schematic page of the charger is attached.
Do you have any thoughts on why this issue is occurring and what kind of fault is being flagged?
Regards
Jeff Coletti
Part Number:BQ25570
I have measured the point that ENout is enabled and it is 2V relative to GND for a sample of 1. This is ideal for our purpose of being driven by a micro directly with a logic level of 3.3V but the datasheet states minimum ENout threshold is VSTOR -0.4V . In this instance VSTOR is 3.85V so it should have required a minimum EN out voltage of 3.45V and the detailed description suggests to use a driver to ENout with level switched to VSTOR potential.
As I need certainty of reliable control can you confirm that a 3.3V drive will consistently enable the ENout in this condition? If I cannot get confirmation I will need to add a non inverting voltage translator to the ENout drive and I would prefer not to add this. Thank you. Barry Wilkins. Sirtrack Ltd.
Hello dear Ti community.
I'm looking for some good step down converter for my power modules which are MeanWell IRM-30-24 // MPM-30-24.
I've got a few question regading this module and potential step down IC.
1) should I use CLC filter at the output of this MeanWell module before I feed step down IC?
2) should I use some kind of filter at the step down IC output (to minimize ripple and noise)?
3) does it make any difference if IC will work at higher freq for eg. 100KHz (PSU module is working at 65KHz).
I'm looking for some rather effective and yet simple solution to avoid linear/LDO regulators due to heat.
Because these in no 18VDC option for this module I'm looking for something that will be able to provide 20VDC that wille be further used for voltage regulators.
I think using LDO/Linear regulator to drop down voltage to desired level will be potentially cheaper but not that effective at all.
Both modules will be used as a bipolar power supply for powering analog IC's like opamps etc.
Thank you for any information and help ;)
Have a nice day.
Part Number:TPS22925
I'm using TPS22925BYPHT which is supposed to have a built in QOD that connects around 150 ohms between the output and ground to drain the output when off. I'm not seeing this happen. Output is off but a floating output is left behind. Several cases of 3.3V leaving behind a floating 900mV level.
Is there a know issue with these parts? I check the markings and they're 12A8 which has the QOD option.
Thanks,
Patryk
Part Number:TPS23755
I am in the process of setting the schematic for a 6W PoE design to revise it due to thermal issues. I could use some wisdom from the TI PoE PD/power supply experts.
I have been looking through the reference designs for TPS23753A, TPS23754 (via TPS23754EVM-420 EVM), and TPS23755, trying to choose between the options.
The TPS23754 seems like a fine option, especially since I have already tested it thermally under load on the bench via the EVM.
Unfortunately, that reference schematic has quite a large number of parts, with the driven SR, opto-coupler, etc.
Our design a little size constrained.
The TPS23753A reference design (PMP9175) is interesting because it has an input & output SR's and not too bad a part count.
But this design does use a smaller transformer, and we expect the transformer to be the biggest contributor, so we want to use something like Coilcraft POE300F-12L or CX9642-AL or JA4387-AL, something rated for much higher power than we intend to conduct.
But the TPS23755 is very attractive due to the low part count and no need for an optocoupler.
I am nominally targetting a +5V output, but converting to +12V and then adding another buck converter to 5V and taking the 5-7% efficiency hit may be worth it to reduce the complexity of the control loop running in the flyback converter.
However, the TPS23755 datasheet says specifically that it is tuned for a diode rectifier on the output.
Does that mean that porting the output SR from the PMP9175 design or applying a UCC24612 (or similar) would not work with the TPS23755?
Can the TPS23755 be operated with a lower inductance transformer and still stably accomplish the primary-side regulation?
Do you expect that the TPS23755 would have serious thermal effects due to its 770mOhm internal MOSFET? We could choose a much higher performance & FOM MOSFET with TPS23753A or TPS23754.
If the subject matter experts on the PoE team had any advice here, it would be greatly appreciated.
We are going to go to prototype as soon as we can get this part selection worked out!
Part Number:BQ24040
Right now we charge our device using the BQ24040, it accepts a USB cable. It runs nicely. Now I'm thinking about introducing solar charging on the device so the idle mode can be offset by solar power. I have been reading the datasheet of the BQ25505, which seems to be a good option. Now my question is, do I need both ICs? Is there an app note showing how to have both functionality, charge by USB and supplement quiescent and sleep mode power drain by using the 25505?
Thanks,
Darren
Part Number:BQ25703A
I have a question about the BQ25703A battery charger. I see that there’s registers I can read via I2C for current, voltage, power, e.g. ADCIBAT() that is an 8-bit digital output of battery charge/discharge current. Could I use this as a fuel gauge? I know this charger supports multiple chemistries - does this part come with “profiles” so it knows which chemistry it’s dealing with?
Brian
Part Number:BQ25713EVM-017
Hello,
We are interested in using BQ25713EVM-017 as a reference design for our product.
Can you please share any project files for Altium?
Part Number:TPS61291
We are trying to use TPS61291 in boost mode only (EN/BYP tied to Vin) using two series alkaline cells to power an MSP430F microcontroller.
The microcontroller changes load from <10uA to approximately 4mA (for 20uS) every 2.5mS.
We observe varying input currents depending on time between powering and not powering (i.e unit is powered and a current is measured after un-powering and applying power again a significantly different current is measured) when trying to measure an average current.
Are there any pitfalls using the TPS61291 in this way?
Part Number:TL431A-Q1
Hi ,
I am working on a Design using TL431 shunt regulator and optocoupler.If input is given 4.7 or less system should conduct and optocoupler collector and emitter should be short .If voltage is greater than 4.7V then system should not conduct.But in my case i have did exactly opposite can any one suggest me to get proper output .PFA of my circuit .
Part Number:BQ40Z50-R2
Hi
I'd like to use some Panasonic UR18650A cells with the battery management chip listed. The chemistry listed for these in the bqStudio software has a capacity of 4250mAh whereas the cells appear to only be available in 2250mAh capacity. Can you please advise on whether this is correct?
Thanks
Daniel
Part Number:UC3710
Hi,
The datasheet for the UCx710 gate drivers mention it to be a low side driver. If I were to use it to drive a high side FET, say for example mosfet in a buck converter, what would be the easiest way to achieve it? A normal solution would be to use a AC coupled transformer to drive the FET. However, the DIP and SOIC packages for the IC have separated power and logic grounds. Does this mean that I can bootstrap the output circuit and use it directly to drive the FET.
Thanks
Nandha
Part Number:LM43601
Requirements +5Vin, -15Vout @ 0.3A
Circuit designed from Webench using these specs. When prototyped, it does not regulate well above 150mA. Even at this modest load, inductor gets hot but -15V is present. Above 150mA, regulation is lost and droops to around -8V. Also this regulator would not start up into a very light load (20mA) without a 22n capacitor connected to the SS pin.