4 ms·

Are other laptop chargers similarly complex? Dell, HP, Microsoft etc

by sosuke 10y ago

revelation 10y ago
Once your power supply is capable of delivering >=75W, european norm 61000-3-2 requires you to implement power factor correction (PFC), which makes complexity balloon. All name-brand laptop chargers will usually have it.
- vonmoltke 10y ago
  > requires you to implement power factor correction (PFC), which makes complexity balloon Depends on how much is required and what your size limits are. Apple used active PFC here to minimize the size of the brick. An ATX desktop or server supply might be able to get away with passive PFC, which is not very complicated but tends to be bulky.
  - TD-Linux 10y ago
    All desktop and server power supplies use active PFC at this point, because the cost of the much bulkier passive components is now higher than the cost of the active ones. EDIT: apparently not quite, I went on Newegg and the non-80plus power supplies still have passive PFC.
    - vonmoltke 10y ago
      Sure, simpler active PFC components are pretty cheap now. There isn't much to a valley-fill circuit, though. That should get you below the legal limit on harmonic distortion in most cases. I know it is still the standard PFC in lower-power fluorescent light ballasts.
unixhero 10y ago
HP chargers / bricks for their high end laptops are pure engineering marvels. http://www.terapeak.com/worth/genuine-hp-elitebook-8760w-8770w-probook-4730s-ac-adapter-power-supply-charger/401148587307/ http://www.terapeak.com/worth/genuine-hp-elitebook-8760w-877...
kens 10y ago
I looked inside an IBM laptop charger and it was considerably simpler than the Apple charger. Since it always outputs power, it doesn't include the microcontroller in the Apple charger. The other circuitry was somewhat simpler (it didn't output multiple voltages), and the IBM charger didn't go to as much effort to be compact.

4 ms·

Are other laptop chargers similarly complex? Dell, HP, Microsoft etc

by sosuke 10y ago

Are other laptop chargers similarly complex? Dell, HP, Microsoft etc

revelation 10y ago
Once your power supply is capable of delivering >=75W, european norm 61000-3-2 requires you to implement power factor correction (PFC), which makes complexity balloon. All name-brand laptop chargers will usually have it.
- vonmoltke 10y ago
  > requires you to implement power factor correction (PFC), which makes complexity balloon Depends on how much is required and what your size limits are. Apple used active PFC here to minimize the size of the brick. An ATX desktop or server supply might be able to get away with passive PFC, which is not very complicated but tends to be bulky.
  - TD-Linux 10y ago
    All desktop and server power supplies use active PFC at this point, because the cost of the much bulkier passive components is now higher than the cost of the active ones. EDIT: apparently not quite, I went on Newegg and the non-80plus power supplies still have passive PFC.
    - vonmoltke 10y ago
      Sure, simpler active PFC components are pretty cheap now. There isn't much to a valley-fill circuit, though. That should get you below the legal limit on harmonic distortion in most cases. I know it is still the standard PFC in lower-power fluorescent light ballasts.
unixhero 10y ago
HP chargers / bricks for their high end laptops are pure engineering marvels. http://www.terapeak.com/worth/genuine-hp-elitebook-8760w-8770w-probook-4730s-ac-adapter-power-supply-charger/401148587307/ http://www.terapeak.com/worth/genuine-hp-elitebook-8760w-877...
kens 10y ago
I looked inside an IBM laptop charger and it was considerably simpler than the Apple charger. Since it always outputs power, it doesn't include the microcontroller in the Apple charger. The other circuitry was somewhat simpler (it didn't output multiple voltages), and the IBM charger didn't go to as much effort to be compact.