Rainbow Electronics MAX1855 - Manual (Page 8)

MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
8 _______________________________________________________________________________________
100
50
0.01 0.1 1 10 100
EFFICIENCY vs.
LOAD CURRENT (1.0V AT 400kHz)
60
MAX1716-09
LOAD CURRENT (A)
EFFICIENCY (%)
70
80
90
85
75
65
55
95
CIRCUIT #3
D2
C2
A2
C1
B1
A1
D1
B2
MAX1716-10
1.50
1.54
1.52
1.58
1.56
1.62
1.60
1.64
0 10 5 15
LOAD CURRENT (A)
20 25
V BATT = 24V
V
BATT
= 7V
OUTPUT VOLTAGE vs. LOAD CURRENT
(1.6V AT 300kHz)
OUTPUT VOLTAGE (V)
PWM MODE
SKIP MODE
1.20
1.24
1.22
1.28
1.26
1.32
1.30
1.34
0 4 6 2 8 10 12 14
OUTPUT VOLTAGE vs.
LOAD CURRENT (1.3V AT 300kHz)
MAX1716-11
LOAD CURRENT (A)
OUTPUT VOTLAGE (V)
CIRCUIT #2
L = 1.0
µH
V BATT = 24V
V BATT = 7V
PWM MODE
SKIP MODE
0.92
0.96
0.94
1.00
0.98
1.02
0 4 6 2 8 10 12 14
OUTPUT VOLTAGE vs.
LOAD CURRENT (1.0V AT 400kHz)
MAX1716-12
LOAD CURRENT (A)
OUTPUT VOTLAGE (V)
CIRCUIT #3
V BATT = 24V
V BATT = 7V
PWM MODE
SKIP MODE
0
100
50
200
150
300
250
350
0 8 4 12 16 20
SWITCHING FREQUENCY
vs. LOAD CURRENT
MAX1716-13
LOAD CURRENT (A)
FREQUENCY (kHz)
PWM MODE
SKIP MODE
V BATT = 7V
V OUT(PROG) = 1.6V
260
280
270
300
290
310
320
0 8 12 4 16 20 24
SWITCHING FREQUENCY
vs. BATTERY VOLTAGE
MAX1716 -14
V BATT (V)
FREQUENCY (kHz)
V OUT(PROG) = 1.6V
V
OUT(PROG)
= 0.925V
I OUT = 12A
270
290
280
310
300
320
330
-40 10 -15 35 60 85
SWITCHING FREQUENCY
vs. TEMPERATURE
TEMPERATURE ( °C)
SWITCHING FREQUENCY (kHz)
MAX1716-15 I OUT = 12A
I OUT = 5A
I OUT = 1A
0.74
0.78
0.76
0.82
0.80
0.86
0.84
0.88
ON-TIME (
µ
s)
MAX1716-16
-40 10 -15 35 60 85
ON-TIME vs. TEMPERATURE
TEMPERATURE ( °C)
I OUT = 12A
I OUT = 5A
I OUT = 1A
-6
-2
-4
2
0
4
6
CURRENT-LIMIT ERROR (%)
MAX1716-17
-40 10 -15 35 60 85
NORMALIZED CURRENT-LIMIT ERROR
vs. TEMPERATURE
TEMPERATURE ( °C)
Typical Operating Characteristics (continued)
(Circuit from Figure 1, components from Table 2, T A = +25°C, unless otherwise noted.)