Sony Fast Charge Car Charger 4.8A CP-CADM2 B
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Official specifications:
- Input: DC 12/24V 3.0A
- Output: 5V 4.8A (2.4A on each output)
- USB outputs: 2
- Weight: 24g
- Size: 28.4 x 68.6 x 28.4mm
I got it from amazon.de
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There is a small round led behind the black plastic above the USB connectors.
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Measurements
- Power consumption when idle is 10.4mA from 12V and 9.3mA from 24V
- Both USB outputs is coded as Apple 2.4A
- It has a white led on the front.
- The +5V is in parallel and there is separate current sense is in the GND lines.
- Weight: 24.3g
- Length: 71mm
- Diameter: 28.5mm
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The USB output can deliver 2.7A, this is fine for a 2.4A rated charger.
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The other output is nearly the same.
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Different input voltage do not change the output current.
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The charger works down to 7V when drawing 2.5A
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The unloaded current draw is fairly independent on voltage.
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I did this test at rated 4.8A current and the charger could handle that.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.
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M1: 50.3°C, M2: 42.1°C, HS1: 61.2°C
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M1: 55.2°C, HS1: 57.7°C
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Noise at 0.5A output is 6mV rms and 79mVpp
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Noise at 1.0A output is 7mV rms and 88mVpp
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Noise at 2.5A output is 6mV rms and 70mVpp, this is very low noise.
Tear down
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I could not get the front of the charger and decided to cut it away.
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On this side we have one inductor and two capacitors.
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The LED is inside black shrink wrap to not light the USB connectors, but only give a small dot on the front.
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At the input is a fuse (F1 X1), the two switching transistors (Q? & Q2: Vs4020AP: 40V 60A 4mOhm), followed by a synchronous switcher chip (U1: AX3070: 40V two current limit input) with two current sense resistors (R15 & R16: 0.033ohm)
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Typical circuit from the datasheet, the charger do not use exactly the same circuit.
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On the front circuit board is resistors for coding, there is no auto coding IC.
Conclusion
This looks like a fairly well designed car charger with lots of current, low noise and individual port protection, but I am missing a auto code chip.
Notes
Read more about how I test USB power supplies/charger
Compare car chargers and other DC supplied chargers