MAX1540A Datasheet, PDF (12/49 Pages) Maxim Integrated Products – Dual Step-Down Controllers with Saturation Protection, Dynamic Output, and Linear Regulator

Dual Step-Down Controllers with Saturation
Protection, Dynamic Output, and Linear Regulator
Typical Operating Characteristics (continued)
(MAX1541 circuit of Figure 12, V_IN = 12V, V_DD = V_CC = 5V, SKIP = GND, TON = REF, T_A = +25°C, unless otherwise noted.)
LINEAR-REGULATOR OUTPUT (LDOOUT)
vs. LOAD CURRENT
3.36
3.34
3.32
3.30
V_LDOIN = 5V
3.28
3.26
V_LDOIN = 12V
3.24
3.22
3.20
0
20
40
60
80
100
LDO LOAD CURRENT (mA)
STARTUP WAVEFORM
(HEAVY LOAD)
MAX1540A toc14
3.3V
A
0
4A
2A
B
0
2.5V
C
0
D
0
400μs/div
A. ON2, 5V/div
B. INDUCTOR CURRENT,
2A/div
C. OUT2, 2V/div
D. PGOOD2, 5V/div
0.5Ω LOAD
STARTUP WAVEFORM
(LIGHT LOAD)
MAX1540A toc15
3.3V
A
0
4A
2A
B
0
2.5V
C
0
D
0
200μs/div
A. ON2, 5V/div
B. INDUCTOR CURRENT,
2A/div
C. OUT2, 2V/div
D. PGOOD2, 5V/div
100Ω LOAD
SHUTDOWN WAVEFORM
(DISCHARGE MODE DISABLED)
MAX1540A toc16
3.3V
A
0
2.5V
B
0
0
C
5V
D
0
5V
E
0
10ms/div
A. ON2, 5V/div
B. OUT2, 2V/div
C. INDUCTOR CURRENT,
2A/div
D. DL2, 5V/div
E. PGOOD2, 5V/div
100Ω LOAD, OVP/UVP = REF OR GND
12 ______________________________________________________________________________________