ltc3400es6-1 Linear Technology Corporation, ltc3400es6-1 Datasheet - Page 4

• Manufacturer Part Number: ltc3400es6-1
• Description: 600ma, 1.2mhz Micropower Synchronous Boost Converter In Thinsot
• Manufacturer: Linear Technology Corporation

BLOCK DIAGRA
LTC3400-1
PI FU CTIO S
SW (Pin 1): Switch Pin. Connect inductor between SW
and V
SW and V
wide as possible to reduce EMI and voltage overshoot. If
the inductor current falls to zero, or SHDN is low, an
internal 100Ω antiringing switch is connected from SW to
V
GND (Pin 2): Signal and Power Ground. Provide a short
direct PCB path between GND and the (–) side of the output
capacitor(s).
FB (Pin 3): Feedback Input to the
Connect resistor divider tap to this pin. The output voltage
can be adjusted from 2.5V to 5V by:
SHDN (Pin 4): Logic Controlled Shutdown Input.
4
IN
V
SHDN = High: Normal free running operation, 1.2MHz
typical operating frequency.
U
to minimize EMI.
OUT
IN
. Optional Schottky diode is connected between
= 1.23V • [1 + (R1/R2)]
1.2MHz
RAMP
GEN
OUT
+
U
SINGLE
CELL
INPUT
. Keep these PCB trace lengths as short and
U
6
V
COMPARATOR
IN
SHDN
W
4
PWM
START-UP
SLEEP
OSC
+
–
–
OPERATION
SHUTDOWN
Burst Mode
CONTROL
CONTROL
CONTROL
SLOPE
g
COMP
PWM
m
Error Amplifier.
C
1µF
IN
A
B
MUX
SHUTDOWN
A/B
SHUTDOWN
R
80k
C
C
150pF
C
4.7µH
CONTROL
L1
DRIVE
SYNC
GOOD
Σ
V
Typically, SHDN should be connected to V
pull-up resistor.
V
Internal Synchronous Rectifier MOSFET. Bias is derived
from V
capacitor(s) should be as short and wide as possible. V
is connected to V
P-channel MOSFET synchronous rectifier.
V
start-up bias from V
comes from V
pletely independent from V
the output power level and the battery’s internal series
resistance.
OUT
OUT
IN
C
2.5pF
+
–
P2
SHDN = Low: Shutdown, quiescent current < 1µA.
100Ω connected between SW and V
to V
chronous rectifier and external inductor.
(Pin 6): Battery Input Voltage. The device gets its
(Pin 5): Output Voltage Sense Input and Drain of the
2.3V
OUT
OUT
1
2
0.35Ω
. PCB trace length from V
through the internal P-channel MOSFET syn-
CURRENT
SENSE
SW
GND
0.45Ω
OUT
ERROR
AMP
g
. Thus, once started, operation is com-
m
IN
(OPTIONAL)
–
+
in shutdown through the internal
IN
SCHOTTKY
OPTIONAL
. Once V
V
C
FB
OUT
5
3
FF
IN
1.23V
REF
. Operation is only limited by
OUT
OUTPUT
OUT
3.3V
R1
1.02M
1%
(EXTERNAL)
R2
604k
1%
(EXTERNAL)
IN
exceeds V
to the output filter
. V
IN
IN
34001 BD
through a 1M
is connected
C
4.7µF
OUT
IN
, bias
34001f
OUT