
4V to 72V Input LDOs with Boost Preregulator
Typical Operating Characteristics (continued)
(V IN = V EN = 14V, C IN = 47μF, C BSOUT = 22μF, C OUT = 10μF, C VL = 1μF, T A = +25°C, unless otherwise noted.) (See Figures 4–7 as
applicable.)
LINE-TRANSIENT RESPONSE
(V IN STEP FROM 4V TO 7V)
MAX5092/93 toc09
LINE-TRANSIENT RESPONSE
(V IN STEP FROM 3.5V TO 72V)
MAX5092/93 toc10
V OUT
I OUT = 250mA
5V (AC-COUPLED)
V IN
50V/div
I OUT = 5mA
72V
50mV/div
7V
3.5V
V IN
V OUT
50mV/div
5V (AC-COUPLED)
1V/div
4V
72V
V BSOUT
1V/div
7V (AC-COUPLED)
V BSOUT
50V/div
7V
200 μ s/div
SWITCHING WAVEFORMS
V BSOUT PROGRAMMED < (V OUT + V BST_DIS )
MAX5092/93 toc11
40ms/div
LINE-TRANSIENT RESPONSE
(V IN STEP FROM 3.5V TO 14V)
MAX5092/93 toc12
V IN
1V/div
V BSOUT
2V/div
5V
(AC-COUPLED)
7V
(AC-COUPLED)
V OUT
100mV/div
5V (AC-COUPLED)
14V
V BSOUT
V OUT
100mV/div
V IN = 5V, I OUT = 100mA,
5V
(AC-COUPLED)
5V/div
7V
14V
V BSOUT PROGRAMMED TO 7V
V IN
I LX
2A/div
100 μ s/div
0
5V/div
200 μ s/div
3.5V
DROPOUT VOLTAGE (V BSOUT - V OUT )
vs. LDO LOAD CURRENT
LDO OUTPUT VOLTAGE
vs. LDO LOAD CURRENT (MAX5092B)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
1000
800
5.15
5.10
T A = -40 ° C: C IN = 10 μ F, C BSOUT = 4.7 μ F, C OUT = 10 μ F
(CERAMIC)
T A = +25 ° C, +135 ° C: C IN = 47 μ F, C BSOUT = 22 μ F
(ELECTROLYTIC), C OUT = 10 μ F (CERAMIC)
0
MAX5092/93 toc15
V IN = 14V, I OUT = 10mA
600
400
200
5.05
5.00
4.95
4.90
T A = +25 ° C, V IN = 4V
T A = +25 ° C, V IN = 14V
T A = -40 ° C, V IN = 4V
T A = -40 ° C, V IN = 14V
T A = +135 ° C, V IN = 4V
T A = +135 ° C, V IN = 14V
-70
10dB/div
0
4.85
0
50
100
150
200
250
0
100
200
300
100
1k
10k
100k
1M
LDO LOAD CURRENT (mA)
LDO LOAD CURRENT (mA)
FREQUENCY (Hz)
6
_______________________________________________________________________________________