Analog Devices ADM8830 b Datasheet

Charge Pump Regulator

TIMING

GENERATOR

LDO

VOLTA

GE

REGULATOR

VOLTA

GE

DOUBLER

CONTROL

LOGIC

DISCHARGE

SHUTDOWN

CONTROL

C1+

C1–

VOUT

LDO IN

+5

VOUT

+5

VIN

C2+

C2–

C3+

C3–

+15VOUT

C4+

C4–

–10VOUT

C1

2.2F

C6

2.2F

C2
1F

C7

2.2F

+5.1V

C3
1F

+15.3V

C8
1F

C4
1F

–10.2V
C9
1F

VOLTA

GE

TRIPLER

DOUBLE

TRIPLE

VOLTAGE

INVERTE

R

OSCILLATOR

CLKIN

SCAN/BLANK

LDO_ON/OFF

SHDN

GND

V

CC

ADM8830

C5

2.2F

for Color TFT Panel

ADM8830

FEATURES
3 Output Voltages (+5.1 V, +15.3 V, –10.2 V) from

One 3 V Input Supply

Power Efciency Optimized for Use with TFT in

Mobile Phones
Low Quiescent Current
Low Shutdown Current (<1 A)
Fast Transient Response
Shutdown Function
Power Saving during Blanking Period
Option to Use External LDO

APPLICATIONS
Handheld Instruments
TFT LCD Panels
Cellular Phones

GENERAL DESCRIPTION

The ADM8830 is a charge pump regulator used for color thin
lm transistor (TFT) liquid crystal displays (LCDs). Using
charge pump technology, the device can be used to generate three
output voltages (+5.1 V ± 2%, +15.3 V, –10.2 V) from a single
3 V input supply. These outputs are then used to provide
supplies for the LCD controller (5.1 V) and the gate drives for
the transistors in the panel (+15.3 V and –10.2 V). Only a few
external capacitors are needed for the charge pumps. An efcient
low dropout voltage regulator also ensures that the power
efciency is high and provides a low ripple 5.1 V output. This
LDO can be shut down and an external LDO used to regulate
the 5 V doubler output and drive the input to the charge pump
section, which generates the +15.3 V and –10.2 V outputs if so
required by the user.

The ADM8830 has an internal 100 kHz oscillator for use in
scanning mode, but the part must be clocked by an external clock
source in blanking (low current) mode. The internal oscillator is
used to clock the charge pumps during scanning mode where the
current is highest. During blanking periods, the ADM8830
switches to use an external, lower frequency clock. This allows the
user to vary the frequency and maximize power efciency during
blanking periods. The tolerances on the output voltages are

REV. B

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
that may result from its use. No license is granted by implication or oth­erwise under any patent or patent rights of Analog Devices. Trademarks
and registered trademarks are the property of their respective owners.

FUNCTIONAL BLOCK DIAGRAM

seamlessly maintained when switching from scanning mode to
blanking mode or vice versa.

The ADM8830 has a number of power saving features, including
low power shutdown and reduced quiescent current consumption
during the blanking periods mentioned above. The 5.1 V output
consumes the most power, so power efciency is also maximized
on this output with an oscillator enabling scheme (Green Idle™).
This effectively senses the load current that is owing and turns
on the charge pump only when charge needs to be delivered to
the 5 V pump doubler output.

The ADM8830 is fabricated using CMOS technology for minimal
power consumption. The part is packaged in 20-lead LFCSP
and TSSOP packages.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] © 2003 Analog Devices, Inc. All rights reserved.

(VCC = 2.6 V to 3.6 V, TA = –40C to +85C, unless otherwise noted, C1, C5, C6,

ADM8830–SPECIFICATIONS

Parameter Min Typ Max Unit Test Conditions

INPUT VOLTAGE, VCC 2.6 3.6 V

SUPPLY CURRENT, ICC 150 400 µA Unloaded, Scanning Period
70 140 µA Unloaded, Blanking Period
1 µA Shutdown Mode, TA = 25°C

+5.1 V OUTPUT
Output Voltage 5.0 5.1 5.2 V IL = 10 µA to 8 mA
Output Current 4 5 mA Scanning Period
5 8 mA Scanning Period, VCC > 2.7 V
50 200 µA Blanking Period
Power Efciency 80 % VCC = 3 V, IL = 5 mA (Scanning)
70 % VCC = 3 V, IL = 200 µA (Blanking)
Output Ripple 10 mV p-p 8 mA Load
Transient Response 5 µs IL Stepped from 10 µA to 8 mA

+15.3 V OUTPUT
Output Voltage 14.4 15.3 15.6 V IL = 1 µA to 100 µA
Output Current 50 100 µA Scanning Period
1 10 µA Blanking Period
Output Ripple 50 mV p-p IL = 100 µA

–10.2 V OUTPUT
Output Voltage –10.4 –10.2 –9.6 V IL = –1 µA to –100 µA
Output Current –100 –50 µA Scanning Period
–10 –1 µA Blanking Period
Output Ripple 50 mV p-p IL = –100 µA

POWER EFFICIENCY 90 % Relative to 5.1 V Output, IL = 100 µA (Scanning)
(+15.3 V and –10.2 V Outputs) 80 % Relative to 5.1 V Output, IL =10 µA (Blanking)

CHARGE PUMP FREQUENCY 60 100 140 kHz Scanning Period

CONTROL PINS
SHDN
Input Voltage, V

0.7 VCC V SHDN High = Normal Mode
Digital Input Current ±1 µA
Digital Input Capacitance* 10 pF
SCAN/BLANK
Input Voltage 0.3 VCC V Low = BLANK Period

0.7 VCC V High = SCAN Period
Digital Input Current ±1 µA
Digital Input Capacitance* 10 pF
LDO_ON/OFF
Input Voltage 0.3 VCC V Low = External LDO

0.7 VCC V High = Internal LDO
Digital Input Current ±1 µA
Digital Input Capacitance* 10 pF
CLKIN
Minimum Frequency 0.9 1 kHz Duty Cycle = 50%, Rise/Fall Times = 20 ns
Input Voltage
VIL 0.3 VCC V
VIH 0.7 VCC V
Digital Input Current ±1 µA
Digital Input Capacitance* 10 pF

*Guaranteed by design. Not 100% production tested.

Specications are subject to change without notice.

0.3 VCC V SHDN Low = Shutdown Mode

SHDN

C7 = 2.2 F, C2, C3, C4, C8, C9 = 1 F, CLKIN = 1 kHz in blanking mode.)

–2–

REV. B

(VCC = 2.6 V to 3.6 V, TA = –40C to +85C, unless otherwise noted, C1, C5, C6,

TIMING SPECIFICATIONS

C7 = 2.2 F, C2, C3, C4, C8, C9 = 1 F, CLKIN = 1 kHz in blanking mode.)

Parameter Min Typ Max Unit Test Conditions

POWER-UP SEQUENCE
+5 V Rise Time, t
+15 V Rise Time, t
–10 V Fall Time, t

300 µs 10% to 90%, Figure 2

R5V

8 ms 10% to 90%, Figure 2

R15V

12 ms 90% to 10%, Figure 2

F10V

Delay between –10 V Fall
and +15 V, t

3 ms Figure 2

DELAY

POWER-DOWN SEQUENCE
+5 V Fall Time, t
+15 V Fall Time, t
–10 V Rise Time, t

Specications are subject to change without notice.

75 ms 90% to 10%, Figure 2

F5V

40 ms 90% to 10%, Figure 2

F15V

40 ms 10% to 90%, Figure 2

R10V

ADM8830

ABSOLUTE MAXIMUM RATINGS*

(TA = 25°C, unless otherwise noted.)

Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +4.0 V

Input Voltage to Digital Inputs . . . . . . . . . . . . . –0.3 V to +4.0 V

Output Short Circuit Duration to GND . . . . . . . . . . . . . 10 sec

Output Voltage

+5.1 V Output . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +6 V

–10.2 V Output . . . . . . . . . . . . . . . . . . . . . . . .–12 V to +0.3 V

+15.3 V Output . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +17 V

Operating Temperature Range . . . . . . . . . . . . –40°C to +85°C

Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.55 W

(Derate 33 mW/°C above 25°C)

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

ESD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Class I

*This is a stress rating only; functional operation of the device at these or any other

conditions above those indicated in the operational sections of this specication is
not implied. Exposure to absolute maximum rating conditions for extended periods
of time may affect reliability.

ORDERING GUIDE

Model Temperature Range Package Description Package Option

ADM8830ACP –40ºC to +85ºC Lead Frame Chip Scale Package CP-20-1
ADM8830ACP-REEL7 –40ºC to +85ºC Lead Frame Chip Scale Package CP-20-1
ADM8830ARU –40ºC to +85ºC Thin Shrink Small Outline Package RU-20
ADM8830ARU-REEL –40ºC to +85ºC Thin Shrink Small Outline Package RU-20
ADM8830ARU-REEL7 –40ºC to +85ºC Thin Shrink Small Outline Package RU-20
EVAL-ADM8830EB Evaluation Board

THERMAL CHARACTERISTICS

20-Lead TSSOP Package:


= 72°C/W

A

J

20-Lead LFCSP Package:


= 31°C/W

A

J

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 ADM8830
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. B

–3–