LTC3035

5

3035f

BLOCK DIAGRA

BIAS

UVLO

BIAS

5V

CP

800kHz

OSCILLATOR

CHARGE

PUMP

EN

REFERENCE

SHDN

0.400V

SOFT-START

BIAS

2.5k

8

1

CM

2

OUT

5

ADJ

6

4

SHDN

7

GND

PINS 3, 9

3035 BD

PI FU CTIO S

CP (Pin 1): Flying Capacitor Positive Terminal.

CM (Pin 2): Flying Capacitor Negative Terminal.

GND (Pin 3): Ground. Connect to a ground plane.

IN (Pin 4): Input Supply Voltage. The output load current

is supplied directly from IN. The IN pin should be locally

bypassed to ground if the LTC3035 is more than a few

inches away from another source of bulk capacitance. In

general, the output impedance of a battery rises with

frequency, so it is usually adviseable to include an input

bypass capacitor when supplying IN from a battery. A

capacitor of 1

µF is usually sufficient.

OUT (Pin 5): Regulated Output Voltage. The OUT pin

supplies power to the load. A minimum ceramic output

capacitor of at least 1

µF is required to ensure stability.

Larger output capacitors may be required for applications

with large transient loads to limit peak voltage transients.

See the Applications Information section for more infor-

mation on output capacitance.

ADJ (Pin 6): Adjust Input Pin. This is the input to the error

amplifier. The ADJ pin reference voltage is 0.4V referenced

to ground. The output voltage range is 0.4V to 3.6V and is

set by connecting ADJ to a resistor divider from OUT to

GND.

SHDN (Pin 7): Shutdown Input, Active Low. This pin is

used to put the LTC3035 into shutdown. The SHDN pin

current is typically less than 10nA. The SHDN pin cannot

be left floating and must be tied to a valid logic level if

not used.

BIAS (Pin 8): BIAS Output Voltage Pin. BIAS is the output

of the charge pump and provides the high side supply for

the LTC3035 LDO circuitry. This pin should be locally

bypassed to ground by a 1

µF or greater capacitor as close

as possible to the pin. Nothing else should be connected

to this pin.

Exposed Pad (Pin 9): Ground and Heat Sink. Must be

soldered to PCB ground plane or large pad for optimal

thermal performance.