Compal NBLB2, Service Manual

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NBLB2 Service Manual
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3. DC-DC CONVERTER
3.1 Description
The DC-DC converter is designed to supply the power for NBLB2 series
notebook computer of Compal. It 5VALWP, +3VALWP, +1.8VSP,
1.05VSP, +1.5VP, +1.1VS_VTTP, +1.0VSP, +0.75VSP, +VGFX_COREP,
+VGA_COREP,
for logical system, + CPU_CORE for CPU and supplies for the
built-in KB926 microprocessor which handles the keyboard and PMU control
functions of the system. The power ON/OFF# is controlled by KB926. There is
also a built-in charger power source. It can charge battery pack whether the
computer is ON or OFF.
3.2 Features
High efficiency, up to 85% (using battery)
Accept wide range DC input voltage from 8V to 19V
Built-in charger power source
The power ON/OFF# is controlled by software
3
.3 Electrical specification
Input Voltage/Current
8V to19V at the summing point of AC-DC and battery
INPUT Current 9.6A max from 6-cell battery
4.74A max from 90W AC-DC Adapter
3.4 Temperature Range:
Operating temperature: 0°C to 40°C
Storage temperature range: - 20°C to 65°C DC/DC OUTPUT
Fixed output voltage/Current
Item +5VALWP +CPU_CORE +VGA_COREP
Nominal voltage +5V depend on VID depend on VID
Min. current 0A 0A 0A
Max. current 5.8A 36A 15.68A
Peak current
8.36A 48A 22.4A
Total regulation 5V±5% depend on VCC static and
Transient Tolerance- VGA_COREP±5%
ripple voltage 200mVp-p max 50mVp-p max@36A 60mVp-p max
Item
+0.75VP +3VALWP +1.1VS_VTTP
Nominal voltage +0.75V +3.3V +1.1V
Min. current 0A 0A 0A
Max. current
0.6A 5.481A 12.6A
Peak current 0.6A 7.83A 18A
Total regulation 0.75V±5% 3.3V±5% 1.05V±5%