Datasheet

(Circuits of Figures 1 (MAX1836) and 2 (MAX1837), V
IN
= 12V, SHDN = IN, T
A
= +25°C.)
70
80
75
90
85
95
100
0 4 8 12 16 20 24
MAX1837EUT33
EFFICIENCY vs. INPUT VOLTAGE
MAX1836/7 toc07
INPUT VOLTAGE (V)
EFFICIENCY (%)
I
OUT
= 10mA
I
OUT
= 200mA
FIGURE 2
V
OUT
= 3.3V
L1 = 47µH
100
1
0 8 12
10
INPUT VOLTAGE (V)
FREQUENCY (kHz)
4
MAX1837EUT33
SWITCHING FREQUENCY vs. INPUT VOLTAGE
16 2420
MAX1836/7 toc08
I
OUT
= 200mA
I
OUT
= 10mA
FIGURE 2
V
OUT
= 3.3V
L1 = 47µH
0
200
600
400
800
1000
0 4 8 12 16 20 24
MAX1837EUT33
PEAK INDUCTOR CURRENT vs. INPUT VOLTAGE
MAX1836/7 toc09
INPUT VOLTAGE (V)
PEAK INDUCTOR CURRENT (mA)
I
OUT
= 10mA
I
OUT
= 200mA
FIGURE 2
V
OUT
= 3.3V
L1 = 47µH
LIMITED BY
t
ON(MIN)
LIMITED BY
I
LIM
4.96
4.98
5.00
5.02
5.04
0 10050 150 200 250 300
MAX1837EUT50
OUTPUT VOLTAGE vs. LOAD CURRENT
MAX1836/7 toc10
LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
V
IN
= 12V TO 24V
V
IN
= 7V
V
IN
= 9V
FIGURE 6
100
95
90
85
80
70
0.1 10 1001 1000
MAX1837EUT50
EFFICIENCY vs. LOAD CURRENT
MAX1836/7 toc11
LOAD CURRENT (mA)
EFFICIENCY (%)
75
V
IN
= 9V
V
IN
= 24V
V
IN
= 18V
V
IN
= 7V
FIGURE 6
V
OUT
= 5V
V
IN
= 12V
200
250
300
350
400
0 100 200 300
MAX1837EUT50
DROPOUT VOLTAGE vs. LOAD CURRENT
MAX1836/7 toc12
LOAD CURRENT (mA)
DROPOUT VOLTAGE (mV)
0
50
100
150
FIGURE 6
V
OUT
= 5V
10
11
12
13
14
15
0 4 8 12 16 20 24
NO-LOAD SUPPLY CURRENT
vs. INPUT VOLTAGE
MAX1836/7 toc13
INPUT VOLTAGE (V)
SUPPLY CURRENT (µA)
Maxim Integrated │ 5
www.maximintegrated.com
MAX1836/MAX1837 24V Internal Switch, 100% Duty Cycle,
Step-Down Converters
Typical Operating Characteristics (continued)