AD ADP3089

PRELIMINARY TECHNICAL DATA
a
1 MHz, 1 A Buck Regulator
ADP3089
Preliminary Technical Data
FEATURES
1 MHz PWM Frequency
Ultrasmall 8-lead 3×3 Sq. mm Chip Scale Package
Automatic PWM to Power Saving Mode at Light Load
Fully Integrated 1.5 A Power Switch
3% Output Regulation Accuracy over Temperature,
Line, and Load
100% Duty Cycle Operation
Simple Compensation
Output Voltage: 1.25 V to 10 V
Small Inductor and MLC Capacitors
Low Quiescent Current while Pulse Skipping
Thermal Shutdown
Fully Integrated Soft Start
Cycle-by-cycle Current Limit
APPLICATONS
PDAs and Palmtop Computers
Notebook Computers
PCMCIA Cards
Bus Products
Portable Instruments
Industrial Systems
FUNCTIONAL BLOCK DIAGRAM
DRV
S Q
R
PROTECTION
LOGIC
(ILIM, OT)
RUN/STOP
COMPARATORS
ERROR
AMP
gm
COMP
FB
GND
+ REF
1.245V
GND
GENERAL DESCRIPTION
The ADP3089’s 1 MHz switching frequency allows for
small, inexpensive external components, and the current
mode control loop is simple to compensate and eases noise
filtering. It operates in PWM current mode under heavy
loads and saves energy at lighter loads by switching automatically into Power Saving mode. Soft start is integrated
completely on chip, as is the cycle-by-cycle current limit.
CURRENT
SENSE
PWM
1MHz
AMP
COMPARATOR
IN
VIN
10µF
The ADP3089 is a high frequency, non-synchronous PWM
step-down DC-DC regulator with an integrated 1.5 A
power switch in a space-saving chip scale package. It provides high efficiency, excellent dynamic response, and is
very simple to use.
SW
IN
ADP3089
SW
IN
0.1µF
IN
DRV
GND
GND
COMP
SOFT-START
TIMER
10µH
20BQ030
VOUT
[email protected]
18.2kΩ
22µF
FB
41.2kΩ
47pF
470pF
10.7kΩ
Figure 1. Typical Application
Capable of operating from 2.5 V to 11 V input with a
typical output current of 1 A, it is ideal for portable, battery powered, industrial, PC and instrumentation applications. Supporting output voltages down to 1.25 V, the
ADP3089 is ideal to generate low voltage rails, providing
the optimal solution in its class for delivering power efficiently, responsively, and simply with minimal printed
circuit board area.
The device is specified over the industrial temperature
range of -40°C to +85°C, and is offered in an ultrasmall 8lead 3×3 square mm chip scale package.
REV. PrE
8/26/02
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
Analog Devices, Inc., 2002
PRELIMINARY TECHNICAL DATA
ADP3089–SPECIFICATIONS1 (V = +3.3 V, T = -40°C to +85°C, unless otherwise noted)
IN
Parameter
SUPPLY
Input Voltage Range
Quiescent Current
Operating
A
Symbol
Conditions
Min
VIN
DRV to GND
2.5
IQ
VIN = 10 V, IL = 1 A,
DRV = GND
No load
VCOMP = 0 V
Shutdown
Ground Current
Normal Operation
ISD
IGND2
Thermal Shutdown Threshold
TSD
Typ
Max
11
12
VIN = 10 V, IL = 1 A,
DRV = 2 V
f SW
D PSM
D MAX
VHYST
FB voltage drops below VREF
OUTPUT SWITCH
Switch On Voltage
VIO3
IL = 1A, FB and DRV tied to
0.75
V
mA
180
15
280
40
µA
µA
3
3.6
mA
160
OSCILLATOR
Oscillator Frequency
Minimum Sleep Duty Cycle
Maximum Duty Cycle
Wake up Hysteresis
Units
°C
1
14
1.25
30
40
MHz
%
%
mV
.7
1.0
V
1.5
1.7
0.5
2
A
µA
1.222
1.245 1.265
.02
V
%/V
-50
35
1
60
20
nA
µA
µA
100
20
GND
Current Limit Threshold
Leakage Current
ERROR AMPLIFIER
Reference Voltage Accuracy
Reference Voltage Line
Regulation
Feedback Input Bias Current
Maximum Output Current
Short Circuit Current
Transconductance
MODULATOR
Transconductance
Control Offset Voltage
Soft Start Time
Shutdown Threshold Voltage
Slope Compensation
ILIM
VIN = 12 V
FB tied to COMP
FB tied to COMP,
VIN = 3 V to 12 V
soft start expired
VREF
I FB
ICOMP,
ICOMP,
gm ,
SC
SD
EA
gm, MOD
VPWM, OS
t SS
VCOMP, SD
mSC
VCOMP = 0 V, activating
shutdown
VFB to ICOMP
VCOMP to IL
480
µA/V
1
0.90
250
A/V
V
µs
mV
A/µs
340
Effectively summed to ISW
50
85
40
0.5
600
750
NOTES
1 All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC).
2 For higher efficiency operation, tie the DRV pin to the output for IL < 250 mA, and V IN > 3 V.
3 V(IN) - V(SW), includes voltage drop across internal current sensor.
Specifications subject to change without notice.
–2–
REV. PrE
PRELIMINARY TECHNICAL DATA
ADP3089
PIN FUNCTION DESCRIPTIONS
ABSOLUTE MAXIMUM RATINGS*
Input Supply Voltage .............................. –0.3 V to +12 V
Voltage on any pin with respect to GND
............................................................ –0.3 V to +12 V
(voltage on any pin may not exceed VIN)
Operating Ambient Temperature Range .. –40°C to +85°C
Operating Junction Temperature ......................... +125°C
θJA (4-layer board) ............................................... 47°C/W
Storage Temperature Range .................. –65°C to +150°C
Lead Temperature Range (Soldering, 10 sec) ..... +240°C
Vapor Phase (60 sec) ........................................ +240°C
Infrared (20 sec) ............................................... +240°C
*This is a stress rating only; operation beyond these limits can cause the device
to be permanently damaged. Unless otherwise specified, all voltages are
referenced to GND.
Pin
Mnemonic
Function
1, 2
IN
3, 6
GND
4
COMP
5
FB
7
DRV
8
SW
Power Supply Input. Both pins
must be connected.
Ground. Both pins must be connected.
Feedback Loop Compensation
and Shutdown Input. An open
drain or collector used to pull
the pin to ground will shutdown
the device.
Feedback Voltage Sense Input.
This pin senses the voltage via
an external resistor divider.
This pin provides a separate
path for drive current to be connected to ground.
Switching Output.
PIN CONFIGURATION
ORDERING GUIDE
Model
Temperature
Range
Package
Option
Branding
Information
ADP3089ACP -40°C to +85°C CSP-8 3×3 P7A
IN
1
IN
2
8
SW
7
DRV
TOP
VIEW*
GND
3
6
GND
COMP
4
5
FB
* PIN’S UNDERSIDE
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 device 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. PrE
–3–
PRELIMINARY TECHNICAL DATA
ADP3089
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
8 Lds Lead Frame Chip Scale Package (LFCSP)
3 × 3 mm Body
(CP-08)
4
3.00 (0.1181)
BSC SQ
0.60 (0.0236)
0.24 (0.0094)
0.50 (0.0197)
0.30 (0.0118)
PIN 1 INDICATOR
1
0.45 (0.0177)
PIN 1
INDICATOR
TOP
VIEW
2.75 (0.1083)
BSC SQ
1.50 (0.059)
REF
0.50 (0.0197)
BSC
BOTTOM
VIEW
0.25 (0.0098)
MIN
0.90 (0.0354) MAX
0.85 (0.0335) NOM
2.25 (0.0886)
2.05 (0.0807)
1.25 (0.0492)
0.95 (0.0374)
DETAIL A
12 MAX
0.70 (0.0276) MAX
0.65 (0.0256) NOM
0.30 (0.0118)
0.18 (0.0071)
COPLANARITY
0.05 (0.0020) MAX
0.01 (0.0004) NOM
SEATING
PLANE
SEATING PLANE
0.20 (0.0079) REF
DETAIL A
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN
–4–
REV. PrE