ltc3526lb-2 Linear Technology Corporation, ltc3526lb-2 Datasheet - Page 6

• Manufacturer Part Number: ltc3526lb-2
• Description: Ltc3526l-2/ltc3526lb-2 - 550ma 2mhz Synchronous Step-up Dc/dc Converters In 2mm ? 2mm Dfn
• Manufacturer: Linear Technology Corporation

LTC3526L-2/LTC3526LB-2
Typical perForMance characTerisTics
SW (Pin 1): Switch Pin. Connect inductor between SW and
V
to reduce EMI. If the inductor current falls to zero or SHDN
is low, an internal anti-ringing switch is connected from
SW to V
GND (Pin 2, Exposed Pad Pin 7): Signal and Power Ground.
Provide a short direct PCB path between GND and the
(–) side of the input and output capacitors. The Exposed
Pad must be soldered to the PCB ground plane. It serves
as an additional ground connection and as a means of
conducting heat away from the package.
V
ceramic decoupling capacitor from this pin to ground
using short direct PCB traces.
pin FuncTions

IN
IN
. Keep PCB trace lengths as short and wide as possible
(Pin 3): Input Supply Pin. Connect a minimum of 1µF
IN
to minimize EMI.
AC-COUPLED
AC-COUPLED
100mV/DIV
100mV/DIV
CURRENT
50mA/DIV
CURRENT
50mA/DIV
LOAD
LOAD
V
V
OUT
OUT
Load Step Response (from Burst
Mode Operation) (LTC3526L-2)
Load Step Response
(Fixed Frequency)
V
V
20mA TO 170mA STEP
C
V
V
50mA TO 100mA STEP
C
IN
OUT
OUT
IN
OUT
OUT
= 3.6V
= 1.2V
= 5V
= 10µF
= 3.3V
= 4.7µF
100µs/DIV
100µs/DIV
3526lb2
3526lb2
G19
G21
SHDN (Pin 4): Logic Controlled Shutdown Input. There
is an internal 4MΩ pull-down on this pin.
FB (Pin 5): Feedback Input to the g
nect resistor divider tap to this pin. The top of the divider
connects to the output capacitor, the bottom of the divider
connects to GND. Referring to the Block Diagram, the output
voltage can be adjusted from 1.5V to 5.25V by:
V
synchronous rectifier. PCB trace from V
filter capacitor (4.7µF minimum) should be as short and
wide as possible.
OUT
• SHDN = High: Normal operation
• SHDN = Low: Shutdown, quiescent current < 1µA
V
OUT
(Pin 6): Output voltage sense and drain of the internal
AC-COUPLED
AC-COUPLED
100mV/DIV
100mV/DIV
50mA/DIV
50mA/DIV
CURRENT
CURRENT
=
1 195
LOAD
LOAD
V
V
T
OUT
.
OUT
A
= 25°C, unless otherwise noted.
Load Step Response (from Burst
Mode Operation) (LTC3526L-2)
Load Step Response
(Fixed Frequency)
V
V
50mA TO 150mA STEP
C
V
V
5mA TO 100mA STEP
C
IN
OUT
OUT
IN
OUT
OUT
V
= 1.2V
= 3.6V
•
= 3.3V
= 10µF
= 5V
= 4.7µF

 
1
+
R
R
2
1
100µs/DIV
50µs/DIV

 
m
Error Amplifier. Con-
OUT
3526lb2
3526lb2
G20
G22
to the output
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