Rainbow Electronics MAX1541 - Manual (Page 13)

MAX1540/MAX1541
Dual Step-Down Controllers with Saturation
Protection, Dynamic Output, and Linear Regulator
______________________________________________________________________________________ 13
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.)
SHUTDOWN WAVEFORM
(DISCHARGE MODE ENABLED)
MAX1540 toc17
3.3V
0
5V
0
B
D
C
A
1ms/div
2.5V
0
0
0
A. ON2, 5V/div
B. OUT2, 2V/div
C. INDUCTOR CURRENT,
2A/div
100 Ω LOAD, OVP/UVP = V
CC OR OPEN
D. DL2, 5V/div
E. PGOOD2, 5V/div
5V
E
2.5V OUTPUT LOAD TRANSIENT
(FORCED PWM)
MAX1540 toc18
4A
0
4A
0
B
D
C
A
40 µs/div
2.5V
2.4V
2.6V
A. I
OUT2
= 0 TO 4A, 5A/div
B. V OUT2 = 2.5V, 100mV/div
SKIP = V
CC
C. INDUCTOR CURRENT, 5A/div
D. LX2, 10V/div
12V
0
2.5V OUTPUT LOAD TRANSIENT
(PULSE SKIPPING)
MAX1540 toc19
4A
0
4A
0
B
D
C
A
40 µs/div
2.5V
2.4V
2.6V
A. I OUT2 = 0.1A TO 4A, 5A/div
B. V OUT2 = 2.5V, 100mV/div
SKIP = GND
C. INDUCTOR CURRENT, 5A/div
D. LX2, 10V/div
12V
0
LINEAR-REGULATOR
LOAD TRANSIENT
MAX1540 toc20
100mA
0
B
A
100 µs/div
3.3V
3.2V
3.4V
A. I LDOOUT = 1mA TO 100mA, 50mA/div
B. V LDOOUT = 3.3V, 100mV/div
SKIP = GND