sc1633cs Semtech Corporation, sc1633cs Datasheet - Page 7

• Manufacturer Part Number: sc1633cs
• Description: Voltage Step-up Dc-dc Converter
• Manufacturer: Semtech Corporation

January 29, 1998
DEVICE OUTLINE - SO-8
PIN DESCRIPTIONS
PIN 1: I
PIN 2: V
PIN 3: SW
PIN 4: SGND Ground connected to the source of the
© 1997 SEMTECH CORP.
LIM
IN
/SD (1) Connected to V
resistor to set the switch peak current.
It serves to protect the IC and induc-
tor, as well as to improve efficiency
and output ripple. However, the supply
capability of the SC1633 is limited by
the current limit resistor (see typical
performance characteristics). The
I
limiting switch peak current is not
required.
(2) The SC1633 goes into shutdown
mode and consumes less than 10µA
when the I
ground.
Input supply.
Drain of the power switch, to be con-
nected to the inductor and diode.
power switch.
LIM
/SD pin should be shorted to V
LIM
/SD pin is pulled to
IN
pin through a
LOW VOLTAGE STEP-UP
DC-DC CONVERTER
IN
if
PIN 5: CGND Ground for control circuits of the IC. It
PIN 6: LBO
PIN 7: LBI
PIN 8: V
PIN CONFIGURATION
652 MITCHELL ROAD NEWBURY PARK CA 91320
OUT
should be separated from SGND to
avoid interference.
Open drain output of the battery low
detector, with 45 Ohm “On Resis-
tance” at V
the voltage on the LBI pin is below
1.22 volts.
The inverting input of the battery low
detector, of which the non-inverting
input is internally connected to the
1.22V voltage reference.
The output voltage feeds back to the
IC through this pin.
IN
=2V. It is pulled low when
SC1633