MAX5053 Maxim Integrated Products, MAX5053 Datasheet - Page 12

• Manufacturer Part Number: MAX5053
• Description: (MAX5052 / MAX5053) Current-Mode PWM Controllers
• Manufacturer: Maxim Integrated Products

Current-Mode PWM Controllers with an Error
Amplifier for Isolated/Nonisolated Power Supplies
12
0V
COMP
V
UVLO
SUPPLY
V
R5
R6
CS
FB
IN
______________________________________________________________________________________
C1
R1
CLAMP
26.1V
V
ERROR
IN
AMP
C2
Typical Operating Circuit
C3
D4
0.3V
VO
V
C5
1.4V
CS
PWM
V
V
COMP
FB
IN
CC
MAX5052
SOFT-START
DIGITAL
R7
UVLO/EN
CPWM
ILIM
NDRV
GND
CS
R2
R3
D1
Q1
REFERENCE
R4
1.23V
T1
MAX5052/MAX5053
C4
D2
OSCILLATOR
262kHz*
V
OUT
21.6V
9.74V
1.28V
1.23V
BOOTSTRAP UVLO
*The MAX5053 does not have an internal bootstrap UVLO. The
MAX5053 starts operation as long as the V
7V (the guaranteed output with a V
the UVLO/EN pin is high.
MAX5052A
MAX5052B
MAX5053A
MAX5053B
UVLO
PART
SHUTDOWN
**
THERMAL
S
R
BOOTSTRAP
Q
*MAX5052A/MAX5053A: 50% MAXIMUM DUTY CYCLE,
**MAX5052 ONLY.
MAX5052B/MAX5053B: 75% MAXIMUM DUTY CYCLE.
UVLO
Yes
Yes
IN
REG_OK
No
No
REGULATOR
(INTERNAL 5.25V SUPPLY)
Functional Diagram
IN
V
STARTUP
VOLTAGE
CC
V
Selector Guide
pin voltage of 10.8V) and
L
10.8V*
10.8V*
22 V
22V
DRIVER
CC
pin is higher than
MAX DUTY
CYCLE
50%
75%
50%
75%
V
NDRV
GND
CC