Analog Devices ADP3000 Datasheet

Micropower Step-Up/Step-Down

COMPARATOR

GAIN BLOCK/
ERROR AMP

400kHz

OSCILLATOR

DRIVER

A1

1.245V

REFERENCE

R1 R2

ADP3000

SET

V

IN

GND SENSE

A0
I

LIM

SW1

SW2

ADP3000-3.3V

1 2

3

8

4

5

I

LIM

V

IN

SW1

FB

(SENSE)

SW2GND

+

100µF

10V

120Ω

6.8µH

IN5817

C1
100µF
10V

V

IN

2V–3.2V

3.3V @
180mA

C1, C2: AVX TPS D107 M010R0100
L1: SUMIDA CD43-6R8

Fixed 3.3 V, 5 V, 12 V and Adjustable

a

High Frequency Switching Regulator

FEATURES
Operates at Supply Voltages from 2 V to 30 V
Works in Step-Up or Step-Down Mode
Very Few External Components Required
High Frequency Operation Up to 400 kHz
Low Battery Detector on Chip
User Adjustable Current Limit
Fixed and Adjustable Output Voltage
8-Pin DIP and SO-8 Package
Small Inductors and Capacitors

APPLICATIONS
Notebook, Palmtop Computers
Cellular Telephones
Hard Disk Drives
Portable Instruments
Pagers

GENERAL DESCRIPTION

The ADP3000 is a versatile step-up/step-down switching
regulator that operates from an input supply voltage of 2 V to
12 V in step-up mode and up to 30 V in step-down mode.

The ADP3000 operates in Pulse Frequency Mode (PFM) and
consumes only 500 µA, making it highly suitable for applica-
tions that require low quiescent current.

The ADP3000 can deliver an output current of 100 mA at
3 V from a 5 V input in step-down configuration and 180 mA at

3.3 V from a 2 V input in step-up configuration.
The auxiliary gain amplifier can be used as a low battery detector,

linear regulator undervoltage lockout or error amplifier.
The ADP3000 operates at 400 kHz switching frequency. This

allows the use of small external components (inductors and
capacitors), making the device very suitable for space constrained
designs.

FUNCTIONAL BLOCK DIAGRAM

Figure 1. Typical Application

V

5V–6V

IN

100µF

R

C1

120Ω

10V

C1, C2: AVX TPS D107 M010R0100
L1: SUMIDA CD43-100

LIM

1 2 3

I

LIM

ADP3000

GND

ADP3000

V

SW1

IN

8

FB

L1

10µH

4

SW2

5

1N5818

D1

100µF

10V

CL

+

R2
150kΩ
1%

R1
110kΩ
1%

V

OUT

3V
100mA

REV. 0

Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.

Figure 2. Step-Down Mode Operation

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] World Wide Web Site: http://www.analog.com
Fax: [phone] © Analog Devices, Inc., 1997

ADP3000–SPECIFICATIONS

(08C ≤ TA ≤ +708C, VIN = 3 V unless otherwise noted)*

ADP3000

Parameter Conditions Symbol Min Typ Max Units

INPUT VOLTAGE Step-Up Mode V

IN

2.0 12.6 V

Step-Down Mode 30.0 V

SHUTDOWN QUIESCENT CURRENT V

COMPARATOR TRIP POINT ADP3000

> 1.43 V; V

FB

> 1.1 × V

SENSE

1

OUTIQ

1.20 1.245 1.30 V

500 µA

VOLTAGE

OUTPUT SENSE VOLTAGE ADP3000-3.3

ADP3000-5
ADP3000-12

2

2

2

V

OUT

3.135 3.3 3.465 V

4.75 5.00 5.25 V

11.40 12.00 12.60 V

COMPARATOR HYSTERESIS ADP3000 8 12.5 mV

OUTPUT HYSTERESIS ADP3000-3.3 32 50 mV

ADP3000-5 32 50 mV
ADP3000-12 75 120 mV

OSCILLATOR FREQUENCY f

DUTY CYCLE V

SWITCH ON TIME I

SWITCH SATURATION VOLTAGE T

STEP-UP MODE V

> V

FB

REF

Tied to VIN, VFB = 0 t

LIM

= +25°C

A

= 3.0 V, ISW = 650 mA V

IN

V

= 5.0 V, ISW = 1 A 0.8 1.1 V

IN

OSC

D6580 %

ON

SAT

350 400 450 kHz

1.5 2 2.55 µs

0.5 0.75 V

STEP-DOWN MODE VIN = 12 V, ISW = 650 mA 1.1 1.5 V

FEEDBACK PIN BIAS CURRENT ADP3000 VFB = 0 V I

SET PIN BIAS CURRENT V

GAIN BLOCK OUTPUT LOW I

REFERENCE LINE REGULATION 5 V ≤ V

= V

SET

REF

= 300 µAV

SINK

V

= 1.00 V

SET

≤ 30 V 0.02 0.15 %/V

IN

I

FB

SET

OL

160 330 nA

200 400 nA

0.15 0.4 V

2 V ≤ VIN ≤ 5 V 0.2 0.6 %/V

GAIN BLOCK GAIN R

GAIN BLOCK CURRENT SINK V

= 100 kΩ

L

≤ 1 V I

SET

CURRENT LIMIT 220 Ω from I

3

LIM

to V

A

V

SINK

IN

I

LIM

1000 6000 V/V

300 µA

400 mA

CURRENT LIMIT TEMPERATURE

COEFFICIENT –0.3 %/°C

SWITCH OFF LEAKAGE CURRENT Measured at SW1 Pin 1 10 µA

V

= 12 V, T

SW1

MAXIMUM EXCURSION BELOW GND T

NOTES

1

This specification guarantees that both the high and low trip point of the comparator fall within the 1.20 V to 1.30 V range.

2

The output voltage waveform will exhibit a sawtooth shape due to the comparator hysteresis. The output voltage on the fixed output versions will always be within the
specified range.

3

100 kΩ resistor connected between a 5 V source and the AO pin.

*All limits at temperature extremes are guaranteed via correlation using standard statistical methods.
Specifications subject to change without notice.

= +25°C

A

I

≤ 10 µA, Switch Off –400 –350 mV

SW1

= +25°C

A

–2–

REV. 0

ADP3000

WARNING!

ESD SENSITIVE DEVICE

1
2
3
4

8
7
6
5

TOP VIEW

(Not to Scale)

ADP3000

I

LIM

V

IN

SW1
SW2

FB (SENSE)*
SET
AO
GND

* FIXED VERSIONS

1
2
3
4

8
7
6
5

TOP VIEW

(Not to Scale)

ADP3000

I

LIM

V

IN

SW1
SW2

FB (SENSE)*
SET
AO
GND

* FIXED VERSIONS

PIN DESCRIPTIONS

Mnemonic Function

I

LIM

For normal conditions this pin is connected to
V

. When lower current is required, a resistor

IN

should be connected between I

LIM

and V

IN.

Limiting the switch current to 400 mA is
achieved by connecting a 220 Ω resistor.

V

IN

Input Voltage.

SW1 Collector of power transistor. For step-down

configuration, connect to V

For step-up

IN.

configuration, connect to an inductor/diode.

SW2 Emitter of power transistor. For step-down

configuration, connect to inductor/diode.
For step-up configuration, connect to ground.
Do not allow this pin to go more than a diode

drop below ground.
GND Ground.
AO Auxiliary Gain (GB) output. The open col-

lector can sink 300 µA. It can be left open

if not used.
SET SET Gain amplifier input. The amplifier’s

positive input is connected to SET pin and its

negative input is connected to 1.245 V. It can

be left open if not used.
FB/SENSE On the ADP3000 (adjustable) version, this pin

is connected to the comparator input. On the

ADP3000-3.3, ADP3000-5 and ADP3000-12,

the pin goes directly to the internal resistor

divider that sets the output voltage.

ABSOLUTE MAXIMUM RATINGS

Input Supply Voltage, Step-Up Mode . . . . . . . . . . . . . . . 15 V

Input Supply Voltage, Step-Down Mode . . . . . . . . . . . . . 36 V

SW1 Pin Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 V

SW2 Pin Voltage . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to V

Feedback Pin Voltage (ADP3000) . . . . . . . . . . . . . . . . . .5.5 V

Switch Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5 A

Maximum Power Dissipation . . . . . . . . . . . . . . . . . . 500 mW

Operating Temperature Range . . . . . . . . . . . . . 0°C to +70°C

Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C

Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . .+300°C

Thermal Impedance

SO-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170°C/W

N-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120°C/W

PIN CONFIGURATIONS

8-Lead Plastic DIP 8-Lead SOIC
(N-8) (SO-8)

ORDERING GUIDE

Output Package

Model Voltage Option

ADP3000AN-3.3 3.3 V N-8
ADP3000AR-3.3 3.3 V SO-8

ADP3000AN-5 5 V N-8
ADP3000AR-5 5 V SO-8

ADP3000AN-12 12 V N-8
ADP3000AR-12 12 V SO-8

ADP3000AN Adjustable N-8
ADP3000AR Adjustable SO-8

N = plastic DIP, SO = small outline package.

IN

SET

V

IN

1.245V

REFERENCE

A2

GAIN BLOCK/
ERROR AMP

A1

COMPARATOR

OSCILLATOR

DRIVER

A0
I

LIM

SW1

SW2

ADP3000

GND FB

Figure 3a. Functional Block Diagram for Adjustable Version

V

IN

1.245V

REFERENCE

Figure 3b. Functional Block Diagram for Fixed Version

SET

A1

GAIN BLOCK/
ERROR AMP

COMPARATOR

R1 R2

GND SENSE

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the ADP3000 features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.

REV. 0

–3–

OSCILLATOR

ADP3000

DRIVER

A0
I

LIM

SW1

SW2

ADP3000

INPUT VOLTAGE – V

1400

0

1.5 3 30

6 9 12 15 18 21 24 27

1200

1000

800

600

400

200

QUIESCENT CURRENT – µA

QUIESCENT CURRENT @ TA = +25°C

R

LIM

– Ω

SWITCH CURRENT – A

1.8

1.6

0

110 1k

100

0.6

0.2

0.4

1.0

0.8

1.4

1.2

TA = +25°C

TA = +85°C

TA = 0°C

VIN = 12V

–Typical Characteristics

2.5

2.0

1.5

1.0

ON VOLTAGE – V

0.5

0

0.1 0.2 1.5

VIN = 5V @ TA = +25°C

VIN = 3V @ TA = +25°C

VIN = 2V @ TA = +25°C

0.4 0.6 0.8 1.0 1.2 1.4
SWITCH CURRENT – A

Figure 4. Switch ON Voltage vs.
Switch Current in Step-Up Mode

406

OSCILLATOR FREQUENCY –

= +25°C

@ T

405

A

404

403

402

401

400

OSCILLATOR FREQUENCY – kHz

399

396

24 306 8 10 12 15 18 21 24 27

INPUT VOLTAGE – V

1.4

VIN = 5V @ TA = +25°C

1.2

1.0

0.8

– V

0.6

CE(SAT)

V

0.4

0.2

0.0

0.1

0.2

VIN = 12V @ TA = +25°C

0.3 0.4 0.5 0.6
SWITCH CURRENT – A

0.8

0.9

Figure 5. Saturation Voltage vs.
Switch Current in Step-Down Mode

0.8
VIN = 5V

0.7

0.6

0.5

0.4

0.3

0.2

SWITCH CURRENT – A

0.1

0

110 1k

TA = +25°C

R

– Ω

LIM

TA = +85°C

TA = 0°C

100

Figure 6. Quiescent Current vs.

Input Voltage

Figure 7. Oscillator Frequency vs.
Input Voltage

1.8
VIN = 3V

1.6

1.4

– Ω

TA = 0°C

100

1.2

TA = +25°C

1.0

0.8

0.6

SWITCH CURRENT – A

0.4

0.2

0

110 1k

Figure 8c. Maximum Switch Current
vs. R

LIM

TA = +85°C

R

LIM

in Step-Up Mode (3 V)

Figure 8a. Maximum Switch Current
vs. R

in Step-Down Mode (5 V)

LIM

440
430
420
410
400
390
380
370
360
350

OSCILLATOR FREQUENCY – kHz

340
330

–40 0 85

TEMPERATURE – °C (TA)

25 70

Figure 9. Oscillator Frequency vs.
Temperature

–4–

Figure 8b. Maximum Switch Current
vs. R

in Step-Down Mode (12 V)

LIM

2.30

2.25

2.20

2.15

2.10

2.05

2.00

ON TIME – µs

1.95

1.90

1.85

1.80
–40 0 85

TEMPERATURE – °C (TA)

25 70

Figure 10. Switch ON Time vs.
Temperature

REV. 0