Datasheet

MAX8597/MAX8598/MAX8599
Low-Dropout, Wide-Input-Voltage,
Step-Down Controllers
_______________________________________________________________________________________ 7
OUTPUT PREBIASED STARTUP
MAX8597 toc07
1ms/div
10V/div
V
LX
V
OUT
V
IN
V
DL
1.0V
1.2V
5V/div
5V/div
STARTUP/SHUTDOWN WITH
EN (I
LOAD
= 20A)
MAX8597 toc08
2ms/div
5V/div
V
POK
I
LX
V
OUT
V
EN
10A/div
1V/div
5V/div
OUTPUT VOLTAGE vs. V
ADJ
(V
IN
= 12V)
MAX8597 toc09
V
ADJ
(V)
OUTPUT VOLTAGE (V)
54321
5
6
7
8
9
10
11
12
13
4
06
CIRCUIT OF FIGURE 1
R
LOAD
= 1.2Ω
ENTERING DROPOUT WAVEFORMS
CIRCUIT OF FIGURE 1
MAX8597 toc10
2µs/div
10V/div
V
LX
V
OUT
V
COMP
V
IN
(AC-COUPLED)
11V
500mV/div
100mV/div
HEAVY-DROPOUT WAVEFORMS
CIRCUIT OF FIGURE 1
MAX8597 toc11
10µs/div
10V/div
V
LX
V
OUT
V
COMP
V
IN
(AC-COUPLED)
11.9V
500mV/div
500mV/div
OUTPUT TRACKING REFIN
MAX8597 toc12
1ms/div
V
REFIN
V
OUT
1V/div
V
REFIN
V
OUT
1V/div
CIRCUIT OF FIGURE 3
5ms RISE
TIME
1ms RISE
TIME
Typical Operating Characteristics (continued)
(Circuit of Figure 4, T
A
= +25°C, 500kHz switching frequency, V
IN
= 12V, unless otherwise noted.)