MB3871 Datasheet, PDF (19/25 Pages) Fujitsu Component Limited. – Mobile Pentium II DC/DC Converter IC

MB3871
s DC/DC CONVERTER SWITCHING OPERATION WAVEFORMS
<VCC = 5 V, VB = 5 V, Vin = 5V>
VS (V)
20
OUT1 (V) OUT2 (V)
60 30 15
50 25 10
40 20
5
30 15
0
20 10 _−5
10 5
00
−10 −5
10 V
5V
0
2
5V
VS
VD3 – VD0 = 0100 (1.8 V)
load: 5 A
fosc = 200 kHz setting
OUT1
OUT2
1 µs
4
6
8
10
t (µs)
expansion
VS (V)
1
OUT1 (V) OUT2 (V)
60 30 0.5
10 V
50 25
0
40 20 _−0.5
30 15 _−1
20 10
10 5
00
−10 −5
5V
500 mV
VS
OUT1
OUT2
100 ns
10 V
500 mV
VS
OUT2
5V
OUT1
100 ns
0
0.2
0.4
0.6
0.8 1.0 0
t (µs)
0.2
0.4
0.6
0.8 1.0
t (µs)
Synchronous rectifier length: 250 ns (typ)
OUT1 tf: 35 ns (typ)
OUT2 tr: 70 ns (typ)
Synchronous rectifier length: 180 ns (typ)
OUT1 tr: 60 ns (typ)
OUT2 tf: 50 ns (typ)
19