Datasheet

MAX17503 4.5V-60V, 2.5A, High-Efciency,
Synchronous Step-Down DC-DC Converter
With Internal Compensation
Maxim Integrated │ 6
www.maximintegrated.com
Typical Operating Characteristics (continued)
(V
IN
= V
EN/UVLO
= 24V, V
PGND
= V
SGND
= 0V, C
VIN
= C
VCC
= 2.2µF, C
BST
= 0.1µF, C
SS
=5600pF,RT=MODE=open,T
A
= T
J
= -40ºC
to +125ºC, unless otherwise noted. Typical values are at T
A
=+25ºC.AllvoltagesarereferencedtoGND,unlessotherwisenoted.)
3.3V OUTPUT, PFM MODE, FIGURE 4b
CIRCUIT
LOAD AND LINE REGULATION
MAX17503 toc10
OUTPUT VOLTAGE (V)
3.2
3.1
3.3
3.4
3.5
3.6
3.0
V
IN
= 36V
200015001000500
0 2500
V
IN
= 12V
LOAD CURRENT (mA)
MODE = OPEN
V
IN
= 48V
V
IN
= 24V
SWITCHING FREQUENCY vs.
RT RESISTANCE
MAX17503 toc11
R
RT
(kΩ)
SWITCHING FREQUENCY (kHz)
908060 7020 30 40 5010
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
2400
0
0 100
SOFT-START/SHUTDOWN FROM EN/UVLO
5V OUTPUT, 2.5A LOAD CURRENT,
FIGURE 4a CIRCUIT
MAX17503 toc12
V
RESET
5V/div
I
OUT
1A/div
V
OUT
2V/div
V
EN/UVLO
2V/div
1ms/div
SOFT-START/SHUTDOWN FROM EN/UVLO
3.3V OUTPUT, 2.5A LOAD CURRENT,
FIGURE 4b CIRCUIT
MAX17503 toc13
V
RESET
5V/div
I
OUT
1A/div
V
OUT
2V/div
V
EN/UVLO
2V/div
1ms/div
SOFT-START/SHUTDOWN FROM EN/UVLO
5V OUTPUT, PFM MODE, 5mA LOAD CURRENT,
FIGURE 4a CIRCUIT
MAX17503 toc14
V
RESET
5V/div
V
OUT
1V/div
V
EN/UVLO
2V/div
2ms/div
MODE = OPEN
SOFT-START/SHUTDOWN FROM EN/UVLO,
3.3V OUTPUT, PFM MODE, 5mA LOAD
CURRENT, FIGURE 4b CIRCUIT
MAX17503 toc15
V
RESET
5V/div
V
OUT
1V/div
V
EN/UVLO
2V/div
2ms/div
MODE = OPEN
5V OUTPUT, PWM MODE
SOFT-START WITH 2.5V PREBIAS,
FIGURE 4a CIRCUIT
MAX17503 toc16
V
RESET
5V/div
V
OUT
2V/div
V
EN/UVLO
2V/div
1ms/div
MODE = SGND
3.3V OUTPUT, PFM MODE
SOFT-START WITH 2.5V PREBIAS,
FIGURE 4b CIRCUIT
MAX17503 toc17
V
RESET
5V/div
V
OUT
1V/div
V
EN/UVLO
2V/div
1ms/div
MODE = OPEN