AIC1631 Datasheet, PDF (6/10 Pages) Analog Intergrations Corporation – 2-Cell, 500mA, Step-Up DC/DC Converter

AIC1631
PIN DESCRIPTIONS
AIC1631/ AIC1631-3 / AIC1631-5
PIN 1: ILIM/SD-
1. Connected to VIN pin
through a resistor to set the
switch peak current. It
serves to protect IC and in-
ductor, as well as to im-
prove efficiency and output
ripples. However, supply
capability of the AIC1631 is
limited by the current limit
resistor. (See typical per-
formance characteristics).
The ILIM/SD pin should be
shorted to VIN pin if limiting
on switch peak current is
not intended.
2. The AIC1631 goes in shut-
down mode and consumes
less than 10µA when
ILIM/SD pin is pulled to
ground.
PIN 2: VIN - Input supply.
PIN 3: SW
- Drain of the power switch, to
be connected to inductor/ di-
ode.
PIN 4:SGND - Ground connected to source of
power switch.
PIN 5:CGND -
Ground for control circuits of
the IC. It should be separated
from SGND to avoid the inter-
ference.
PIN 6:LBO
- Open drain output of the bat-
tery low detector, with 45Ω
“ON resistance” at V_IN=2V. It is
pulled low when the voltage on
LBI pin is below 1.22V.
PIN 7:LBI
- The noninverting input of the
battery low detector, of which
the inverting input is internally
connects to 1.22V voltage ref-
erence.
PIN 8:VOUT - The output voltage feedbacks
to the IC through this pin.
AIC1631A
PIN 1: ILIM/SD-
PIN 2: VIN -
PIN 3: SW -
PIN 4: GND -
PIN 5: FB -
PIN 6: LBO -
1. Connected to VIN pin
through a resistor to set the
switch peak current. It serves to
protect IC and inductor, as well
as to improve efficiency and
output ripples. However, supply
capability of the AIC1631A is
limited by the current limit resis-
tor. (See typical performance
characteristics). The ILIM/SD pin
should be shorted to VIN pin if
limiting on switch peak current is
not intended.
2. The AIC1631A goes in shut-
down mode and consumes less
than 10µA when ILIM/SD pin is
pulled to ground.
Input supply.
Drain of the power switch, to be
connected to inductor/ diode.
Ground.
Output voltage can either be
internally set to 5 volt by
grounding FB pin, or be exter-
nally set to an arbitrary voltage
by applying to FB pin the divider
voltage of two divider resistors.
VOUT voltage is given by the
following equation:
R1
R2
=
VOUT
0.617
−1
where R1 = Resistor connected
between FB pin and VOUT pin.
R2= Resistor connected be-
tween FB pin and ground.
VOUT=Output voltage to be set.
Open drain output of the battery
low detector, with 45Ω “ON re-
sistance” at V_IN=2V. It is pulled
low when the voltage on LBI pin
is below 1.22V.
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