Compal NBLB2 - Under voltage protection; Short circuit protection

NBLB2 Service Manual
66
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 supply +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%