@madaboutears it's a MOSFET but still not an easy find. You can try TaoBao or Alibaba (not AliExpress). Here is what I got:
PN6013 Integrated standby power consumption quasi-resonant primary-side controller and high avalanche
Capability Intelligent PowerMOSFET, used for high-performance, peripheral components
Streamlined charger, adapter and built-in power supply. PN6013for
Primary side feedback working mode, optocoupler andTL431. Built-in high
The voltage start circuit can realize the no-load loss of the chip (230VAC)Small
At50mW. In constant voltage mode, using quasi-resonant and multi-mode technology
Remove audio noise so that the system satisfies6level energy efficiency standard, adjustable
The output line compensation function can enable the system to obtain better load regulation;
In constant current mode, the output current and power can be passedCSpin resistance
Make adjustments. The chip provides intelligent protection features, including week-by-week over-current protection, over-voltage protection, open-loop protection, over-temperature protection, output out short circuit protection andCSOpen/short circuit protection, etc
built-in700VHigh Avalanche Capability Smart PowerMOSFET--PN6013
Recommended Products
I. Overview
PN6013Integrated standby power consumption quasi-resonant primary-side controller and high avalanche capability smart powerMOSFET, for high-performance chargers, adapters and built-in power supplies with reduced peripheral components.PN6013 It is the primary side feedback working mode, and the optocoupler andTL431. Built-in startup circuit can realize chip no-load loss (230VAC) is less than50mW. In constant voltage mode, quasiresonance and multi-mode technology are used to remove audio noise, making the system meet6Class energy efficiency standards, the adjustable output line compensation function allows the system to obtain better load regulation; in constant current mode, the output current and power can beCSThe resistance of the pin is adjusted. The chip provides intelligent protection functions, including cycle-by-cycle over-current protection, over-voltage protection, open-loop protection, over-temperature protection, output short-circuit protection andCSOpen/short circuit protection, etc.
POWER MOSFET--
Two characteristics
built-in700VHigh Avalanche Capability Smart PowerMOSFET Built-in starting circuit, less than50mWLoad loss(230VAC) adopts quasi-resonance and multimode technology to meet6level energy efficiency standards
Full voltage input range±5%ofCC/CVAccurate primary side feedback can save optocoupler andTL431
Constant voltage, constant current, and output line compensation are externally adjustable
No additional compensation capacitor required
No audio noise
Intelligent protection function
Over temperature protection (OTP)
VDDUndervoltage & overvoltage protection (UVLO&OVP)
Cycle-by-cycle overcurrent protection (OCP)
CSOpen/short circuit protection (CS O/SP) Open
loop protection (OLP)
Applications
switching power adapter
battery charger
Set top box power supply
Standby power consumption primary side feedback AC to DC conversion
Quad package
You may get a good answer on Reddit but if you don't I would check with Digikey.com or Mouser.com. Use whatever little data is here to see if you can find an equivalent. Digikey has a good forum that deals a lot with identifying and cross-referencing components.
If you are creative and don't mind changing some of the circuitry, you could try a DK910 (same package, different pinout) or you can again use the data from that and check with the before mentioned places and hunt for an equivalent.
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4 Comments
http://www.zm699.com/Products/nz700vgxbn...
by Augustine
Hi @madaboutears
What's the frequency of the 5V output?
To me you are describing a "pulsing" 5V AC output or if you like if the frequency is high enough it is effectively a 5V DC output with a small ripple - bad example maybe but see first waveform diagrams in link
Is this the voltage that is required on the output?
by jayeff
Hi jayeff, thanks for your interest.
The whole purpose of this simple little power supply is to deliver 5v 300mA DC from 90 to 240v AC mains. Just like other USB power-source-from-the-mains units. It does that at the moment but only in short bursts about 45 times a minute. A very weird fault.
by William
@madaboutears
I think that you would need to increase the frequency by altering the IC on/off timing.
At the moment the output is about .75Hz i.e. 60 seconds ÷ 45 so not exactly replicating DC. Usually smps frequency is in the KHz range but it may depend on the design of the circuit and the IC being used
Without seeing the datasheet for the IC I would imagine that the on/off timing would be determined by the 22K Ohm / 1.5 Ohm resistor divider network and the 4.3K ohm resistor + capacitor across the input side.
by jayeff