150W DC/DC POWER SUPPLY FOR CARPC
1  Function Description
DC/DC ATX power supply for automobile application, 6-32VDC input, +5V,+12V,+3.3V,-12V,+5VSB and PG (power good signal) outputs.
2  Operation Environment
Item Unit Minimum Typical Maximum Test Conditon
Temperature ?äðDIV> -20   50   
RH %RH 40   90 No Condensation  

3 Technique Requirement
3.1 Input Characteristic
Item Unit Minimum Typical Maximum Test Conditon
DC INPUT Vdc 6 24 32   
Input Current A 6   30   
  

3.2  Output Characteristic
3.2.1  Output Voltage Regulation
Output Min. Load Max. Load Peak Load Output Voltage range Ripple??pk-pk????rated load??20MHz limit??*
+5V 0.5A 10A   4.75~5.25V 50mV
+12V 0.3A 6A 6A 11.40~12.60V 120mV
+3.3V 0.5A 10A   3.14~3.55V 50mV
-12V 0A 0.2A   -11.0~-13.2V 120mV
+5VSB 0.1A 2A 3A 4.75~5.25V 100mV


*: Need to add 47?̆ tantalum capacitor and 0.1?̆ high frequency capacitor on test point when testing.
3.2.2 Others Output Characteristics
Item Unit Minimum Typical Maximum Test Conditon
Output Power W     150 DC output power  
Efficiency %   90   Rated load
            
Turn on Overshoot %     10   
Rise Time ms   20   Output voltage up from 0% to 95%??rated load
Hold up Time ms   2   Rated load

3.3  EMC Requirement
Item Request Standard Judgement Grade
Conducted interference  CLASS B, 3dB margin EN55022 Ensure system pass the CLASS B and have 3dB margin
Radiation interference CLASS B, 3dB margin EN55022 Ensure system pass the CLASS B and have 3dB margin

3.4  Protection Function
Item Unit Yes/No Minimum Typical Maximum Recovery Characteristic  
Input invertion protection   Yes         
+5V OVP V Yes 5.8   6.8 Latched, need to re-apply DC input to recovery
+12V OVP V Yes 13.2   15.6 Latched
+3.3V OVP V Yes 3.9   4.3 Latched
Short CircuitProtection??+5V,+12V,+3.3V??   Yes       Lached

4  Monitoring ,Signal Control
4.1 Process Sequence
Item Name Characteristic
1

  Power good signal
??PG?? The PG signal comes from the  No. pin8 of the 20pin output connector, it indicate the power supply working condition, this ??TTL?? signal is the result of ??AND?? relationship with DC output and DC input voltage . On working condition, if the DC input voltage is well within it??s operation range, then the PG signal is sent out (PG is in H logic) after 100-500ms delay. If the DC input voltage down and below to 11V, or the one of DC output voltage out of it??s normal range, then send out Power Fall signal (that is: PG is in L logic). The Power Fall signal fall to below 0.3V, should have 1ms (at least) before the +5V output down to 4.5V,. And the PG signal??s slop during the rise up and fall down
Should be smooth and no any oscillation happened.  PG signal should have the capacity to drive 6 standard TTL loading.
  
2

  Sleeping mode control
(ON/OFF) The ON/OFF signal comes from the  No. pin14 of the 20pin output connector, is to control the power supply??s working state. (Be active in ??L?? level). If the ON/OFF signal is in floating, the power supply will have no output (except 5VSB ) and in sleeping mode . The 5VSB should be within the range of 4.75-5.25V under 1.5A loading condition, and no any audible noise can be heard. If the ON/OFF signal is shorted to ground, the power supply will be in normal working condition and have normal output voltage.