Step-Down Controllers with
Synchronous Rectifier for CPU Power
MAX796/MAX797/MAX799
_____________________________________Typical Operating Circuits (continued)
FROM
REF
INPUT 6V TO 30V
V+
SECFB
SHDN
FB
VL
–5V
OUTPUT
MAX799
DH
BST
+5V
OUTPUT
LX
DL
SS
REF
GND
SYNC
PGND
CSH
CSL
__________________________________________Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
EFFICIENCY
vs. LOAD CURRENT, 5V/3A CIRCUIT
MAX796-01
EFFICIENCY
vs. LOAD CURRENT, 3.3V/3A CIRCUIT
MAX796-02
EFFICIENCY
vs. LOAD CURRENT, 3.3V/10A CIRCUIT
SKIP = LOW
90
EFFICIENCY (%)
MAX796-03
100
V
IN
= 6V
100
V
IN
= 5V
90
EFFICIENCY (%)
V
IN
= 12V
80
V
IN
= 30V
100
90
EFFICIENCY (%)
V
IN
= 30V
80
80
SKIP = HIGH
70
60
50
40
STANDARD MAX797 3.3V/10A
CIRCUIT, FIGURE 1
f = 300kHz
V
IN
= 5V
0.1
1
LOAD CURRENT (A)
10
70
STANDARD MAX797 5V/3A
CIRCUIT, FIGURE 1
f = 300kHz
0.001
0.01
0.1
1
10
70
STANDARD MAX797 3.3V/3A
CIRCUIT, FIGURE 1
f = 300kHz
0.001
0.01
0.1
1
10
60
60
50
LOAD CURRENT (A)
50
LOAD CURRENT (A)
6
_______________________________________________________________________________________