Datasheet

MAX796/MAX797/MAX799
Step-Down Controllers with
Synchronous Rectifier for CPU Power
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MAX473
V+
INPUT
4.5V
TO 30V
Q1
Si9433DY
OR MMSF4P01
82pF
VL (5V)
20pF
1k
100k, 1% 1.5k
16k, 1%
REF
(2.505V)
MAIN
3.3V
OUTPUT
(CSL)
+3.3V
MAIN OUTPUT
+2.9V OUTPUT
AT 2A
STANDARD 3.3V
CIRCUIT
10µF10µF
MAX797
SANYO OS-CON
Figure 14. 2.9V Low-Dropout Linear Regulator with Fast Transient Response
MAX797
CSL
CSH
VL
SYNC
REF
GND
V+
Q1
FB
100k
100k
+5V AT 1A
BST
DH
LX
DL
PGND
2N7002
OPTIONAL SYNC AND LOW-VOLTAGE
START-UP CIRCUIT
SKIP
SHDN
V
IN
2.5V TO 5.25V
C2
100µF
C3
100µF
0.33µF
0.033
0.01µF
C1
100µF
D1
1N4148
190kHz - 340kHz
1N4148
+3.3V
(EXTERNAL)
33k
4.7µF
L1
5µH
0.1µF
L1 = SUMIDA CDRH125, 5µH
D1 = MOTOROLA MBR130
C1 - C3 = AVX TPS 100µF, 10V
Q1 = SILICONIX Si9936 (BOTH SECTIONS)
OR MOTOROLA MMDF3N03L
Figure 15. Low-Noise Boost Converter for Cellular Phones
____________________________________________Application Circuits (continued)