Charge Pump Regulator for Color TFT Panel Data Sheet ADM8832 FEATURES FUNCTIONAL BLOCK DIAGRAM 3 output voltages (+5.1 V, +15.3 V, 10.2 V) from one 3 V C5 2.2F input supply V CC Power efficiency optimized for use with TFT in mobile C1+ ADM8832 VOLTAGE C1 phones C1 DOUBLER 2.2F VOUT Low quiescent current LDO IN Low shutdown current (<1 A) OSCILLATOR CLKIN C6 LDO Fast transient response 2.2F VOLTAGE SCAN/ Shutdown function REGULATOR BLANK +5VOUT CONTROL Power saving during blanking period +5VIN LOGIC +5.1V LDO ON/ Option to use external LDO C7 C2+ OFF DOUBLE C2 2.2F C2 1F C3+ TRIPLE C3 APPLICATIONS TIMING C3 1F GENERATOR Handheld instruments +15VOUT VOLTAGE +15.3V TFT LCD panels TRIPLER C8 C4+ C4 1F Cellular phones VOLTAGE C4 1F SHUTDOWN INVERTER SHDN DISCHARGE CONTROL 10VOUT 10.2V C9 GND 1F Figure 1. GENERAL DESCRIPTION The ADM8832 is a charge pump regulator used for color thin mode where the current is highest. During blanking periods, film transistor (TFT) liquid crystal displays (LCD). Using charge the ADM8832 switches to an external, lower frequency clock. pump technology, the device can be used to generate three This allows the user to vary the frequency and maximize power output voltages (+5.1 V 2%, +15.3 V, 10.2 V) from a single efficiency during blanking periods. The tolerances on the output voltages are seamlessly maintained when switching from scan- 3 V input supply. These outputs are then used to provide supplies for the LCD controller (+5.1 V) and the gate drives for ning mode to blanking mode or vice versa. the transistors in the panel (+15.3 V and 10.2 V). Only a few The ADM8832 power saving features include low power external capacitors are needed for the charge pumps. An shutdown and reduced quiescent current consumption during efficient low dropout voltage regulator also ensures that the the blanking periods. The 5.1 V output consumes the most power efficiency is high and provides a low ripple 5.1 V output. power, so power efficiency is also maximized on this output This LDO can be shut down and an external LDO used to with an oscillator enabling scheme (Green Idle). This regulate the 5 V doubler output and drive the input to the effectively senses the load current that is flowing and turns on charge pump section, which generates the +15.3 V and 10.2 V the charge pump only when charge needs to be delivered to the outputs if so required by the user. 5 V pump doubler output. The ADM8832 has an internal 100 kHz oscillator for use in The ADM8832 is fabricated using CMOS technology for minimal scanning mode, but the part must be clocked by an external power consumption. The part is packaged in a 20-lead LFCSP clock source in blanking (low current) mode. The internal (lead frame chip scale package). oscillator is used to clock the charge pumps during scanning Rev. 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Technical Support www.analog.com OBSOLETE 03759-A-001ADM8832 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Pin Configuration and Function Descriptions ..............................6 Applications ....................................................................................... 1 Typical Performance Characteristics ..............................................7 Functional Block Diagram .............................................................. 1 Theory of Operation ...................................................................... 10 General Description ......................................................................... 1 Scanning and Blanking .............................................................. 10 Revision History ............................................................................... 2 Power Sequencing ...................................................................... 10 Specifications ..................................................................................... 3 Transient Response .................................................................... 10 Timing Specifications .................................................................. 4 External Clock ............................................................................ 10 Absolute Maximum Ratings ............................................................ 5 Outline Dimensions ....................................................................... 11 Thermal Characteristics .............................................................. 5 Ordering Guide .......................................................................... 11 ESD Caution .................................................................................. 5 REVISION HISTORY 8/2017Rev. A to Rev. B Changed CP-20 to CP-20-6 .......................................... Throughout Updated Outline Dimensions ....................................................... 11 Changes to Ordering Guide .......................................................... 11 4/2004Rev. 0 to Rev. A Updated Outline Dimensions ....................................................... 11 Changes to Ordering Guide .......................................................... 11 7/2003Revision 0: Initial Version Rev. B Page 2 of 12 OBSOLETE