MAX16801A Datasheet, PDF (14/15 Pages) Maxim Integrated Products – Off-Line and DC-DC PWM Controllers for High-Brightness LED Drivers

Off-Line and DC-DC PWM Controllers for
High-Brightness LED Drivers
Functional Diagram
IN
UVLO
COMP
FB
CS
IN
CLAMP
26.1V
DIGITAL
SOFT-START
REFERENCE
1.23V
BOOTSTRAP UVLO**
21.6V
9.74V
1.28V
1.23V
UVLO
IN
VCC
REGULATOR
REG_OK
V_L
(INTERNAL 5.25V SUPPLY)
ERROR
AMP
V_OPWM
1.38V
CPWM
V_CS
0.3V
LIM
*OSCILLATOR
264kHz
S
Q
R
THERMAL
SHUTDOWN
DRIVER
MAX16801
MAX16802
*MAX16801A/MAX16802A: 50% MAXIMUM DUTY CYCLE
MAX16801B/MAX16802B: 75% MAXIMUM DUTY CYCLE
**MAX16801 ONLY
VCC
NDRV
GND
Selector Guide
PART
BOOTSTRAP
UVLO
STARTUP
VOLTAGE
(V)
MAX DUTY
CYCLE (%)
MAX16801A
Yes
22
50
MAX16801B
Yes
22
75
MAX16802A
No
10.8*
50
MAX16802B
No
10.8*
75
*The MAX16802 does not have an internal bootstrap UVLO.
The MAX16802 starts operation as long as the VCC pin is high-
er than +7V, (the guaranteed output with an IN pin voltage of
+10.8V), and the UVLO/EN pin is high.
TOP VIEW
Pin Configuration
UVLO/EN 1
DIM/FB 2
COMP 3
CS 4
MAX16801
MAX16802
8 IN
7 VCC
6 NDRV
5 GND
µMAX
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