ADP1614

Data Sheet

Rev. 0 | Page 10 of 16

THEORY OF OPERATION

The ADP1614 current-mode, step-up switching converter

boosts a 2.5 V to 5.5 V input voltage to an output voltage as

high as 20 V. The internal switch allows a high output current,

and the 650 kHz/1.3 MHz switching frequency allows the use of

tiny external components. The switch current is monitored on a

pulse-by-pulse basis to limit the current to the value set by the

SW

PWM

COMPARATOR

UVLO

COMPARATOR

TSD

COMPARATOR

OSCILLATOR

S

R

Q

D

COMPARATOR

+

+

VIN

VIN

CURRENT

SENSING

DRIVER

BAND GAP

N1

BG

RESET

1.1MΩ

AGND

ERROR

AMPLIFIER

2

1

5.5µA

COMP

SS

FB

R1

R2

8

L1

D1

A

6

SW

7

3

9

5

GND

4

GND

11

EP

AGND

EN

CLRES

ADP1614

10

>1.6V

<0.3V

SOFT

START

Figure 25. Block Diagram with Step-Up Regulator Application Circuit