1308AI Linear Technology Corporation, 1308AI Datasheet - Page 6

• Manufacturer Part Number: 1308AI
• Description: Lt1308b - Single Cell High Currentmicropower 600khz Boost Dc/dc Converter
• Manufacturer: Linear Technology Corporation

LT1308A/LT1308B
V
Connect a series RC from this pin to ground. Typical
values are 47kΩ and 100pF. Minimize trace area at V
FB (Pin 2/Pin 2): Feedback Pin. Reference voltage is
1.22V. Connect resistive divider tap here. Minimize trace
area at FB. Set V
SHDN (Pin 3/Pin 3): Shutdown. Ground this pin to turn
off switcher. To enable, tie to 1V or more. SHDN does not
need to be at V
GND (Pin 4/Pins 4, 5, 6, 7): Ground. Connect directly to
local ground plane. Ground plane should enclose all
components associated with the LT1308. PCB copper
connected to these pins also functions as a heat sink. For
the TSSOP package, connect all pins to ground copper to
get the best heat transfer. This keeps chip heating to a
minimum.
PIN
6
C
V
U
(Pin 1/Pin 1): Compensation Pin for Error Amplifier.
OUT
FUNCTIONS
= 1.22V(1 + R1/R2).
U
IN
OUT
to enable the device.
U
according to:
(SO/TSSOP)
C
.
SW (Pin 5/Pins 8, 9, 10): Switch Pins. Connect inductor/
diode here. Minimize trace area at these pins to keep EMI
down. For the TSSOP package, connect all SW pins
together at the package.
V
bypass capacitor right at the pins, connected directly to
ground. For the TSSOP package, connect both V
together at the package.
LBI (Pin 7/Pin 13): Low-Battery Detector Input. 200mV
reference. Voltage on LBI must stay between –100mV
and 1V. Low-battery detector does not function with
SHDN pin grounded. Float LBI pin if not used.
LBO (Pin 8/Pin 14): Low-Battery Detector Output. Open
collector, can sink 50μA. A 220kΩ pull-up is recom-
mended. LBO is high impedance when SHDN is grounded.
IN
(Pin 6/Pins 11, 12): Supply Pins. Must have local
IN
1308abfa
pins