Datasheet

LTC3526L/LTC3526LB
7
3526lfc
3
+
–
+
–
GATE DRIVERS
AND
ANTI-CROSS
CONDUCTION
LOGIC
CLK
I
PK
I
PK
COMP
SLOPE
COMP
I
ZERO
COMP
ERROR AMP
SLEEP COMP
I
ZERO
WAKE
EXPOSED
PAD
+
–
WELL
SWITCH
MODE
CONTROL
UVLO
V
REF
V
REF
4M
SHDN
V
BEST
START-UP
1MHz
OSC
TSD
THERMAL
SHUTDOWN
SHUTDOWN
ANTI-RING
V
SEL
V
IN
1
6
SW
V
OUT
L1
4.7µH
V
B
SHUTDOWN
CLAMP
C
SS
V
REF
V
OUT
5
7
GND
3526l BD
2
FB
R2
C
OUT
4.7µF
V
OUT
1.5V
TO 5.25V
R1
4
C
IN
2.2µF
V
IN
0.8V
TO 5V
block DiAgrAM
(Refer to Block Diagram)
operAtion
The LTC3526L/LTC3526LB are 1MHz synchronous boost
converters housed in a 6-lead 2mm × 2mm DFN
package.
With a guaranteed ability to start up and operate from inputs
less than 0.8V, this device features fixed frequency, current
mode PWM control for exceptional line and load regula
-
tion. The current mode architecture with adaptive slope
compensation provides excellent transient load response,
requiring minimal output filtering. Internal soft-start and
internal loop compensation simplifies the design process
while minimizing the number of external components.
With its low R
DS(ON)
and low gate charge internal N-chan-
nel MOSFET switch and P-channel MOSFET synchronous
rectifier, the LTC3526L achieves high efficiency over a wide
range of load currents. Burst Mode operation maintains
high efficiency at very light loads, reducing the quiescent
current to just 9µA. Operation can be best understood by
referring to the Block Diagram.
LOW VOLTAGE START-UP
The LTC3526L/LTC3526LB include an independent start-
up oscillator designed to start up at an input voltage of
0.68V (typical). Soft-start and inrush current limiting are
provided during start-up, as well as normal mode.
When either V
IN
or V
OUT
exceeds 1.3V typical, the IC
enters normal operating mode. When the output voltage