Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [pmic]

13 questions
3
votes
4 answers

Why is NMI commonly pulled high on many ARM SoC schematics?

I've noticed that "AP-NMI" is pulled high on several ARM SoC schematics, and it is pulled high by the real-time clock (RTC) voltage, which is an always-on power domain (battery backup). Why is this? I've also noticed that without NMI being pulled…
Drakes
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2
votes
2 answers

Single chip power good IC?

It seems like there should be a million chips for this, but for the life of me can't find any. I'm looking for a small (SOT23 or similar size if possible) IC that provides an active high when the supply voltage goes ABOVE a setpoint, and open…
Mutski
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2
votes
2 answers

BJT collector-emitter breakdown voltage

I'm developing a flyback converter with the FT838NB1 IC, and I got some doubts about the collector-emitter breakdown voltage of the integrated NPN switching transistor. Absolute maximum ratings show that the collector to GND voltage can go to…
Maurício Tochetto
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1
vote
1 answer

How to connect in serial two 2S Battery pack but charge them seperately?

I want to create a circuit that has input 12V DC and uses this voltage both charging two 2S (7.4V Li-Ion without balancing wire with BMS Circuit on the pack) batteries and at the same time supplying energy to the load. When 12V DC is not connected…
torosluadam
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1
vote
1 answer

Solder pad with no copper circles inside?

I'm trying to use a ROHM BD9F800MUX (buck PMIC regulator with synchronous regulation.) Upon looking at their footprint guide, it has something I have not seen before and is poorly documented. It appears they have a large solder pad with 3 circles…
MadHatter
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1
vote
0 answers

MP2617H(PMIC) is not working

I am designing a PCB board for our vehicle tracking device. Here the device will track GPS location and send it to the user. This is a battery operated device. Our power station provides us 12v input voltage and by using this we want to charge our…
Aarav Soni
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0
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0 answers

Charging voltage across VM and VSS of AP9221SA-CC-HAC-7 is 0.6V even when USB charger is inserted

I am using AP9221SA-CC-HAC-7 PCM IC with 1-cell Li-ion battery (4.2V). I have battery charger (RT9471) after PCM IC and load connected after battery charger. The PACK+ and PACK- signals go the the battery charger supply pins. Load is never…
Vedashree
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0
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PMIC using AP9221SA-CC-HAC-7 not allowing charging

I am using AP9221SA-CC-HAC-7 PCM IC with 1-cell Li-ion battery (4.2V). I have battery charger (RT9471) after PCM IC and load connected after battery charger. The PACK+ and PACK- signals go the the battery charger supply pins. Load is never…
Vedashree
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0
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0 answers

PMIC MIC23451 operating voltage range

I am using Microchip SOM module in my project. Not using all the things in the SOM. So we are redesigning the board with necessary components for my application. Below is block diagram shows the main power flow. Output from PMIC1 (MIC23451) is…
Hari
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Do I need a PMIC on an ESP32 audio player?

I am designing a small audio player for my daughter, based on a TTGO T-Display. It will have a few buttons for control and to select playlists. It will have an SD card reader and two MAX98357 amplifiers for stereo sound. This is a partial picture of…
francisaugusto
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0 answers

Use power supply from Coral SOM or obtain from DCDC Converter?

I'm designing a carrier board for Coral SOM. DCDC_3V3 and VDDA_1V8 are SOM outputs, according with Google, they are using PMIC BD71837MWV to get this outputs, but they are not using them in their carrier board, using other DCDC dual channel…
Juanma
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0
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1 answer

TPS65233 LNB Circuit is drawing more current from supply

I have used LNB controller TPS65233 in my design. Input is 5.5V and Output: 13/18V. I am seeing access current drawn by the circuit when I give 5.5V input to the circuit and no load is connected to the output. Manually I have checked and there is no…
ABSTONE
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3 answers

Interpreting thermal shutdown threshold values from TPS659037

I'm studying the datasheet of TI TPS659037 PMIC. The MIN / TYP / MAX values are throwing me off here. Are these 3 numbers indicating variations between every IC manufactured?
Adam Lee
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