Is Ambrane safe now? 30W GaN Charger Teardown & analysis: Checking the quality after the Gyan Therapy video
Ambrane's reputation took a serious hit after a Gyan therapy's video their power bank/charger combo that literally exploded under normal use also damaging more things around it . Like many others, I avoided Ambrane products after that, but out of curiosity, I went ahead and purchased their 25/30W GaN charger specifically to test its safety and design. To my surprise, it is actually quite well-made. Here is an overview of my findings:
Pros -
- Transformer - The transformer secondary (safe DC voltage part) is triple insulated many cheap ones only the thin lacquer (enamel) on the wire itself for separation which has a high chance of coming in contact with the primary (high voltage AC counterpart) this transformer uses triple-insulated wiring for the secondary side. This provides a robust physical barrier between the high-voltage AC and the safe DC output (img2)
- Synchronous Rectification - Instead of a schottky diode a proper synchronous rectifier is used for output rectification which basically uses a MOSFET with a control circuitry to the simulate a diode (ideal) nearly eliminating the voltage drop of a normal silicon diode (img3)
- Creepage - Because it is very small and compact the thing i was also worried of AC-DC separation it was hard to do that ,but they have handled it pretty well by using a plastic part and a slot between it so the creepage distance might be small but it is well separated (img4) (img5)
- EMI suppression - Most fly-back SMPS have a capacitor between the primary and secondary to provide a return path for high frequency common mode noise generated due to switching now since it is between primary and secondary it is safety critical so a specialized one should be used many cheap ones use a normal one to save on cost but this one uses a proper class Y1 (img6)
- Power ratings - it does what it claims. refer to the image for more info (img7)
Cons -
The main drawback is the lack of primary-side EMI suppression. To save on cost and space (though the footprint would only have increased by ~15%), they omitted: (img8)
- MOV (Metal Oxide Varistor): Essential for surge protection.
- Class-X1 Capacitors & Common Mode Choke: These filter out high-frequency noise.
Why this matters: Without these, you might notice flickering on sensitive electronics (like monitors or TVs) or touch-ghosting on your phone if they are plugged into the same circuit as this charger.
Technical Observations
- Fuse - instead of a glass fuse a box type slow blow fuse is used which is more reliable and has better manufacturing tolerances (img9)
- Main IC - it is a OB2733V which according to it's datasheet is a PWM controller with a integrated 650v GaN MOSFET the datasheet does not mention the continuous drain current (Id) of the mosfet for some reason but it it mentions the wattage as - 25w meaning Ambrane is pushing it slightly at the 30W peak. It was also covered with some thermal clay for better heat dissipation (img10)
- Construction- The Usb c port it is mounted on a separate board along with the communication IC which is not a good or a bad thing just a design decision (img11 & img12)
Final Verdict: 7/10
Surprisingly, it is a well engineered product even tough it lacks EMI filtering , the core safety features (insulation, Y-caps, and creepage) are all present and accounted for and the BIS certification appears valid
It is safe to use✅
Note: This is a completely different design from their failed power bank combo, and this teardown/analysis does not mean all other Ambrane products are either safe or unsafe. This analysis only applies to this specific 30W model