DC-DC Converter SCI7661C0B/M0B. 95% Typical Power Efficiency Doubled or Tripled Output Voltage Internal Voltage Regulator DESCRIPTION FEATURES

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1 PF0-0 Low Voltage Operation Products SCIC0B/M0B DC-DC Converter % Typical Power Efficiency Doubled or Tripled Output Voltage Internal Voltage Regulator DESCRIPTION The SCIC0B/M0B CMOS DC-DC Converter features high operational performance with low power dissipation. It consists of two major parts: the booster circuitry and the regulator circuitry. The booster generates a doubled output voltage (-.V to -V) or tripled output voltage (-.V to -V) from the input (-. to -V). The regulator is capable of setting the output to any desired voltage. The regulated voltage can be given one of the three threshold temperature gradients. FEATURES High performance with low power dissipation Simple conversion of VI (-V) to VI (V), VI (0V), VI (-0V) or VI (-V) On-chip output voltage regulator Power conversion efficiency Typ.% Temperature gradient for LCD power supply 0.%/ C, -0.%/ C or -0.%/ C Power off by external signals Stationary current at power off Max. µa Cascade connection two device connected: VI = -V, VO = -0V) On-chip C-R oscillator Package... SCIC0B: DIP-pin (plastic) SCIM0B: SOP-pin (plastic) SCIMBB: SSOP-pin (plastic) BLOCK DIAGRAM OSC OSC VI CAP CAP CAP CAP CR Oscillator Voltage Converter (I) Voltage Converter (II) Reference Voltage Generator Voltage Regulator Temperature Gradient Select circuit TC TC Poff RV VO Booster Regulator

2 SCIC0B/M0B PIN CONFIGURATION PIN DESCRIPTION Pin name No. Function CAP CAP CAP CAP TC TC VI 0 OSC OSC Poff RV VO The same pin configuration in DIP and SOP CAP, CAP-, Terminal for connection of capacitor for doubler CAP, CAP-, Terminal for connection of capacitor for tripler TC, TC, Temperature gradient selection terminal VI Power supply terminal (negative, system supply GND) VO Output terminal at tripling Regulated voltage output terminal RV 0 Regulated voltage control terminal Poff Vreg output ON/OFF control terminal OSC, OSC, Oscillation resistor connection terminal Power supply terminal (positive system supply VCC) ABSOLUTE MAXIMAM RATINGS ( = 0V) Rating Symbol Min. Max. Unit Remark Input supply voltage VI -0/N 0. V Input terminal voltage VI N = : Doubler N = : Tripler VI V OSC, Poff VO V TC, TC, RV Output voltage VO -0.0 V Allowable loss Pd 00 mw Operating temperature Topr -0 C Plastic package Storage temperature Tstg - 0 C Soldering temperature and time Tsol 0 C, 0s (at lead) Note: When this IC is soldered in the solder-reflow process, be sure to maintain the reflow furnace at the curve shown in Fig. - Temperature Profile for Standard SMD Package (QFP, SOP, PLCC and etc.) of this DATA BOOK. And this IC can not be exposed to high temperature of the solder dipping. ELECTRICAL CHARACTERISTICS ( = 0V, VI = -V, Ta = -0 to C) Characteristic Symbol Min. Typ. Max. Unit Condition Input supply voltage VI V VO -.0 V Output voltage RL =, RRV = MΩ V VO = -V Regulator operating voltage VO V Booster current consumption Iopr 0 0 µa RL =, ROSC = MΩ Regulator current RL =, RRV = MΩ Iopr.0.0 µa consumption VO = -V Stationary current IQ.0 µa TC = TC = VO, RL = Oscillation frequency fosc 0 khz ROSC = MΩ Output impedamce ROUT 0 00 Ω IO = 0mA Booster power conversion efficiency Peff 0 % IO = ma Regulated output voltage -V < VO < -V 0. %/V fluctuation VO = -V, RL =, Ta = C

3 SCIC0B/M0B Characteristic Symbol Min. Typ. Max. Unit Condition VO = -V, = -V, Regulated output.0 Ω Ta = C load fluctuation IO 0 < IO < 0mA, TC = TC = VO RSAT = ( - VO) / IO Regulated output saturation resistance RSAT.0 Ω 0 < IO < 0mA, RV =, Ta = C VRV TC = VO, TC =, Ta = C Reference voltage VRV V TC = TC = VO, Ta = C VRV TC =, TC = VO, Ta = C CT CT = (0 C) - (0 C) Temperature Gradient CT %/ C 0 C - 0 C CT ( C) 00 Input leakage current IL.0 µa Poff, TC, TC, OSC, RV pins RECOMMENDED OPERATING CONDITIONS (Ta = -0 to C) Condition Symbol Min. Max. Unit Remark Booster start voltage VSTA -. V ROSC = MΩ, C * CL/C /0, Ta = -0 to C Booster stop voltage VSTP -. V ROSC = MΩ Output load resistance RL RL Min.* Ω Output load current IOUT 0 ma Oscillation frequency fosc 0 0 khz Extarnal resistance for oscillation ROSC kω Capacitor for booster C,C,C. µf Regulated output adjustable resistance RRV kω *: Recommended circuity in low voltage operation is shown below (VI =.V to.v) RL Min. depends on input voltage as shown below. C= C= 0 = MΩ RL CL RLmin ( kω) C=µF D(VF(IF=mA) 0.V) VI (V)

4 SCIC0B/M0B CIRCUIT DESCRIPTION C-R Oscillator The SCIC0B/M0B contains a C-R oscillator for internal oscillation. It consists of an external resistor ROSC connected between the OSC pin and OSC pin. Voltage Converters OSC OSC External Clock OSC OSC Open C-R Oscillation External Clock Operation The voltage converters double/triple the input supply voltage (VI) using clocks generated by the C-R oscillator. VCC (V) GND VI=V VI=V (V) CAP-=VI=0V Typical Doubled Voltage Relations VO= VI=V Typical Tripled Voltage Relations Reference Voltage Generator and Voltage Regulator The reference voltage generator produces reference voltage needed for operation of regulator circuit. The voltage regulator is used to regulate a boosted output voltage and its circuit contains a power-off function which uses signals from the system for on-off control of the Vreg output. Poff RV Voltage Regulator Control signal RRV=00kΩ to MΩ Temperature Gradient Selector Circuit The SCIC0B/M0B provides the output with a temperature gradient suitable for LCD driving. (between and ) Temperature Gradient Assignment Poff TC TC Temp. Gradient Output CR oscillation Remarks () L(VO) L(VO) -0.%/ C ON ON L H() -0.%/ C ON ON H() L -0.%/ C ON ON H H -0.%/ C ON OFF Cascade connection 0(VI) L L OFF (Hi-Z) OFF 0 L H OFF (Hi-Z) OFF 0 H L OFF (Hi-Z) OFF 0 H H OFF (Hi-Z) ON Without regulation Note: The potential at Low level is different between the Poff pin and the TC/TC pin.

5 SCIC0B/M0B BASIC EXTERNAL CONNECTION Voltage Doubler and Tripler A doubled voltage can be obtained at VO (CAP-) by disconnecting capacitor C from the tripler configuration and shorting CAP- (pin ) and VO (pin ). Voltage Tripler Regulator output is given a temperature gradient, after boosted output VO regulated. In this connection, both VO and can be taken out at the same time. V VI=V C C 0 C Voltage Tripler MΩ VO=V V VI=V C C MΩ 0 Shield wire VO= V C RRV 00kΩ to MΩ C Tripler Regulator (-0.%/ C selected as temperature gradient) =V= RRV VRV R Parallel Connection Parallel connections of n circuits can reduce Rout to about /n, that output impedance Rout can be reduced by connecting serial configuration. A single smoothing capacitor C can be used commonly for all parallely connected circuit. In parallely connection, a regulated output can be obtained by applying the regulation circuit to only one of the n parallely connected circuit. V VI=V C C 0 MΩ C C C 0 Parallel Connection MΩ C RRV 00k to M VO=V =0V Cascade Connection Cascade Connection of SCIC0B/M0B (by connecting VIN and VOUT of one stage to and VI respectively of the next stage) further increase the output voltage. Note, however, that the serial connection increases the output impedance. =VI=V V VI=V 0 MΩ VO= 0VVI 0 VO=0V 00kΩ to MΩ =V Serial Connection

6 SCIC0B/M0B Positive Voltage Conversion The input voltage can be doubled or tripled toward the positive side. (In the doubler configuration, capacitor C and diode D are disconnected and the diode D shorted at the both ends.) In this case, however, the output voltage decrease by VF (forward voltage). For example = 0V, VI = -V and VF =.0V, then VO = 0V - 0.V =.V (if doubled, V - 0.V =.V) V VI=V D D D VO=.V C C C 0 MΩ Positive Voltage Conversion D, D, D: Shottky diodes with small VF are recommended. Negative Voltage Conversion Positive Voltage Conversion This circuit produces outputs of -V and.v from the -V input. Note that this configuration causes higher output impedance than in a single function (negative or positive voltage converter.) VI=V V VO=.V MΩ 0 VO =V =V VI=0V VO=.V VO=0V Negative Voltage Conversion Positive Voltage Conversion Changing the Temperature Gradient through Use of External Temperature Sensor (Thermistor) The SCIC0B/M0B has a temperature gradient selector circuit in its regulator. It selects any one of the three gradients: -0.%/ C, -0.%/ C and -0.%/ C. Itis necessary that the temperature gradient can be changed to any other value by connecting a thermistor in series to the output voltage control resistor RRV. 0 R RRV RT RP PACKAGE DIMENSIONS Example of Change of Temperature Gradient Plastic DIP-pin.max (0.max) ±0. (0. ±0.00 ). ±0.. ±0. (0. ±0.00 ) 0.00 ( ). (0.0) 0. ± ( ) min (0.min) 0. ± (0.) (0.0 ) 0. (0.) (0.0 ) Unit : mm (inch)

7 SCIC0B/M0B Plastic SOP-pin 0.max (0.max) 0. ± (0.0 ) INDEX. ± ( ) ±0. (0. ±0.0 ).max (0.0max). (0.0) 0. ± (0.00 ). ±0. (0.0 ±0.00 ) 0. ± (0.0 ) 0. ±0.0 (0.00 ±0.00 ) 0. (0.0). (0.0) Unit : mm (inch) NOTICE: No part of this material may be reproduced or duplicated in any form or by any means without the written permission of Seiko Epson. Seiko Epson reserves the right to make changes to this material without notice. Seiko Epson does not assume any liability of any kind arising out of any inaccuracies contained in this material or due to its application or use in any product or circuit and, further, there is no representation that this material is applicable to products requiring high level reliability, such as, medical products. Moreover, no license to any intellectual property rights is granted by implication or otherwise, and there is no representation or warranty that anything made in accordance with this material will be free from any patent or copyright infringement of a third party. This material or portions thereof may contain technology or the subject relating to strategic products under the control of the Foreign Exchange and Foreign Trade Law of Japan and may require an export license from the Ministry of International Trade and Industry or other approval from another government agency. Seiko Epson Corporation 000 All right reserved. All other product names mentioned herein are trademarks and/or registered trademarks of their respective companies. ELECTRONIC DEVICES MARKETING DIVISION IC Marketing & Engineering Group ED International Marketing Department I (Europe, U.S.A) - Hino, Hino-shi, Tokyo -0, JAPAN Phone: 0 FAX: 0 Electronic devices information on the Epson WWW server. ED International Marketing Department II (ASIA) - Hino, Hino-shi, Tokyo -0, JAPAN Phone: 0 FAX: 00 First issue February, 000 Printed in Japan H