TCM680 +5V TO ±10V VOLTAGE CONVERTER GENERAL DESCRIPTION FEATURES APPLICATIONS ORDERING INFORMATION

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1 EVALUATION KIT AVAILABLE FEATURES 99% Voltage onversion Efficiency 85% Power onversion Efficiency Wide Voltage Range...0V to 5.5V Only 4 External apacitors Required Space Saving 8-Pin SOI Design APPLIATIONS ±10V From 5V Logic Supply ±6V From a 3V Lithium ell Handheld Instruments Portable ellular Phones LD Display Bias Generator Panel Meters Operational Amplifier Power Supplies ORDERING INFORMATION Part No. Package Temperature OA 8-Pin SOI 0 to 70 PA 8-Pin Plastic DIP 0 to 70 EOA 8-Pin SOI 40 to 85 EPA 8-Pin Plastic DIP 40 to 85 T7660EV harge Pump Family Evaluation Kit GENERAL DESRIPTION The is a dual charge pump voltage converter that develops output voltages of and from a single input voltage of.0v to 5.5V. ommon applications include ±10V from a single 5V logic supply, and ±6V from a 3V lithium battery. The is packaged in a space-saving 8-pin SOI package and requires only four inexpensive external capacitors. The charge pumps are clocked by an on-board 8kHz oscillator. Low output source impedances (typically 150Ω) provides maximum output currents of 10mA for each output. Typical power conversion efficiency is 85%. High efficiency, small installed size and low cost make the suitable for a wide variety of applications that need both positive and negative power supplies derived from a single input voltage. PIN ONFIGURATIONS (DIP AND SOI) PA EPA TYPIAL OPERATING IRUIT 5V.0V< < 5.5V OA EOA V OUT = (x ) V OUT = ( x ) Microchip Technology Inc. DS1486A - 9/5/96

2 ABSOLUTE MAXIMUM RATINGS* V V OUT V V OUT V V OUT Short-ircuit Duration... ontinuous V OUT urrent...75ma dv/dt... 1V/µsec Power Dissipation (T A 70 ) Plastic DIP...730mW Small Outline...470mW Storage Temperature to 150 Lead Temperature (Soldering, 10 sec) *Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or other conditions above those indicated in the operation section of the specification is not implied. Exposure to the Absolute Maximum Ratings conditions for extended periods of time may affect device reliability. ELETRIAL HARATERISTIS: = 5V, T A = 5, test circuit Figure 1, unless otherwise indicated. Symbol Parameter Test onditions Min Typ Max Unit Supply Voltage Range MIN. T A MAX., R L = kω to V Supply urrent = 3V, R L = ma = 5V, R L = 1 = 5V, 0 T A 70, R L =.5 = 5V, 40 T A 85, R L = 3 Negative harge Pump Output I L = 10mA, I L = 0mA, = 5V Ω Source Resistance I L = 5mA, I L = 0mA, =.8V I L = 10mA, I L = 0mA, = 5V: 0 T A T A Positive harge Pump Output I L = 10mA, I L = 0mA, = 5V Ω Source Resistance I L = 5mA, I L = 0mA, =.8V I L = 10mA, I L = 0mA, = 5V: 0 T A T A F OS Oscillator Frequency 1 khz P EFF Power Efficiency R L = kω 85 % E FF Voltage onversion Efficiency V OUT, R L = %, R L = Microchip Technology Inc. reserves the right to make changes in the circuitry or specifications detailed in this manual at any time without notice. Minimums and maximums are guaranteed. All other specifications are intended as guidelines only. Microchip Technology Inc. assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement. PIN DESRIPTION 8-Pin DIP/SOI Symbol Description 1 3 Input. apacitor 1 negative terminal. Input. apacitor positive terminal. Input. apacitor negative terminal. 4 V OUT Output. Negative output voltage ( ). 5 Input. Device ground. 6 Input. Power supply voltage. 7 Input. apacitor 1 positive terminal. 8 V OUT Output. Positive output voltage ( ) VOUT 7 1 VOUT V 6 IN R L R L - 9/5/96 Figure 1. Test ircuit 001 Microchip Technology Inc. DS1486A

3 DETAILED DESRIPTION Phase 1 charge storage The positive side of capacitors and are connected to 5V at the start of this phase. 1 is then switched to ground and the charge in 1 is transferred to. Since is connected to 5V, the voltage potential across capacitor is now 10V. SW1 SW 5V = 5V 4 SW3 3 SW4 V DD Phase 4 SW1 SW 5V = 5V 4 SW3 3 SW4 Figure 4. harge Pump Phase 3 V DD V DD transfer The fourth phase of the clock connects the negative terminal of to ground, and transfers the generated 10V across to 4, the V DD storage capacitor. Again, simultaneously with this, the positive side of capacitor is switched to 5V and the negative side is connected to ground, and the cycle begins again. Figure. harge Pump Phase 1 5V Phase transfer Phase two of the clock connects the negative terminal of to the storage capacitor 3 and the positive terminal of to ground, transferring the generated 10V to 3. Simultaneously, the positive side of capacitor is switched to 5V and the negative side is connected to ground. SW1 SW 4 SW3 3 SW4 10V V DD 5V 4 SW1 SW3 V DD 3 SW SW4 10V Figure 3. harge Pump Phase Figure 5. harge Pump Phase 4 MAXIMUM OPERATING LIMITS The has on-chip zener diodes that clamp to 5.8V, V OUT to 11.6V, and V OUT to 11.6V. Never exceed the maximum supply voltage or excessive current will be shunted by these diodes, potentially damaging the chip. The will operate over the entire operating temperature range with an input voltage of V to 5.5V. Phase 3 V DD charge storage The third phase of the clock is identical to the first phase the charge transferred in produces 5V in the negative terminal of, which is applied to the negative side of capacitor. Since is at 5V, the voltage potential across is 10V. 001 Microchip Technology Inc. DS1486A 3-9/5/96

4 EFFIIENY ONSIDERATIONS Theoretically a charge pump can approach 100% efficiency under the following conditions: The charge Pump switches have virtually no offset and extremely low on resistance Minimal power is consumed by the drive circuitry The impedances of the reservoir and pump capacitors are negligible For the, efficiency is as shown below: Efficiency V = V DD /( ) VDD = V DROP V DROP = (I OUT)(R OUT) Efficiency V = /( ) VSS = V DROP V DROP = (I OUT)(R OUT) Power Loss = (V DROP)(I OUT) (V DROP)(I OUT) There will be a substantial voltage difference between (V OUT ) and for the positive pump and between V OUT and V OUT if the impedances of the pump capacitors and are high with respect to the output loads. Larger values of reservoir capacitors 3 and 4 will reduce output ripple. Larger values of both pump and reservoir capacitors improve the efficiency. See "apacitor Selection" in Applications Section. APPLIATIONS Positive and Negative onverter The most common application of the is as a dual charge pump voltage converter which provides positive and negative outputs of two times a positive input voltage. The simple circuit of Figure 6 performs this same function using the and external capacitors,,, 3 and 4. apacitor Selection The requires only 4 external capacitors for operation. These can be inexpensive polarized aluminum electrolytic types. For the circuit in Figure 6 the output characteristics are largely determined by the external capacitors. An expression for R OUT can be derived as shown below: R OUT = 4(R SW1 R SW ESR 1 R SW3 R SW4 ESR ) 4(R SW1 R SW ESR 1 R SW3 R SW4 ESR ) 1/(f PUMP x 1) 1/(f PUMP x ) ESR 4 R OUT = 4(R SW1 R SW ESR 1 R SW3 R SW4 ESR ) 4(R SW1 R SW ESR 1 R SW3 R SW4 ESR ) 1/(f PUMP x 1) 1/(f PUMP x ) ESR 3 Assuming all switch resistances are approximately equal... R OUT = 3R SW 8ESR 1 8ESR ESR 4 1/(f PUMP x 1) 1/(f PUMP x ) R OUT = 3R SW 8ESR 1 8ESR ESR 3 1/(f PUMP x 1) 1/(f PUMP x ) R OUT is typically 140Ω at 5 with = 5V and 1 and as low ESR capacitors. The fixed term (3R SW ) is about 130Ω. It can be seen easily that increasing or decreasing values of 1 and will affect efficiency by changing R OUT. However, be careful about ESR. This term can quickly become dominant with large electrolytic capacitors. Table 1 shows R OUT for various values of 1 and (assume 0.5Ω ESR). 1 and 4 must be rated at 6VD or greater while and 3 must be rated at 1VD or greater. Output voltage ripple is affected by 3 and 4. Typically the larger the value of 3 and 4 the less the ripple for a given load current. The formula for V RIPPLE(p-p) is given below: µf V RIPPLE(p-p) = {1/[(f PUMP /3) x 4] (ESR 4 )}(I OUT) V RIPPLE(p-p) = {1/[(f PUMP /3) x 3] (ESR 3 )}(I OUT) µf µf 3 µf For a (0.5Ω ESR) capacitor for 3, 4, f PUMP = 1kHz and I OUT = 10mA the peak-to-peak ripple voltage at the output will be less than 100mV. In most applications (I OUT < = 10mA) 10-0µF output capacitors and 1-5µF pump capacitors will suffice. Table shows V RIPPLE for different values of 3 and 4 (assume 1Ω ESR). Figure 6. Positive and Negative onverter - 9/5/ Microchip Technology Inc. DS1486A

5 Table 1. R OUT vs. 1, 1, (µf) R OUT (Ω) Table. V RIPPLE (p-p) vs. 3, 4 (I OUT = 10mA) 3, 4 (µf) V RIPPLE (mv) Paralleling Devices Paralleling multiple s reduces the output resistance of both the positive and negative converters. The effective output resistance is the output resistance of a single device divided by the number of devices. As illustrated in Figure 7, each requires separate pump capacitors and, but all can share a single set of reservoir capacitors. ±5V Regulated Supplies From A Single 3V Battery Figure 8 shows a complete ±5V power supply using one 3V battery. The provides 6V at V OUT, which is regulated to 5V by the T55, and 5V by the negative LDO. The input to the can vary from 3V to 6V without affecting regulation appreciably. With higher input voltage, more current can be drawn from the outputs of the. With 5V at, 10mA can be drawn from both regulated outputs simultaneously. Assuming 150Ω source resistance for both converters, with (I L I L ) = 0mA, the positive charge pump will droop 3V, providing 7V for the negative charge pump. V OUT V NEGATIVE OUT SUPPLY OUT µf Figure 7. Paralleling for Lower Output Source Resistance 001 Microchip Technology Inc. DS1486A 5-9/5/96

6 3V OUT µf 6V 6V µf OUT T55RP500Exx NEGATIVE LDO 1µF 1µF 5 SUPPLY GROUND 5 SUPPLY T54V70Exx LOW BATTERY Figure 8. Split Supply Derived from 3V Battery - 9/5/ Microchip Technology Inc. DS1486A

7 TYPIAL HARATERISTIS 300 V OUT or Output Resistance vs. 4 = 10.0 V OUT or V OUT vs. Load urrent VIN = 5V OUTPUT RESISTANE (Ω) R OUT (V) (V) LOAD URRENT (ma) SUPPLY URRENT (ma) Supply urrent vs. NO LOAD (V) Output Voltage vs. Output urrent From to = 5V (V) OUTPUT URRENT (ma) From TO 001 Microchip Technology Inc. DS1486A OUTPUT SOURE RESISTANE (Ω) Output Source Resistance vs. Temperature = 5V I OUT = 10mA R OUT TEMPERATURE ( ) 7-9/5/96

8 PAKAGE DIMENSIONS 8-Pin Plastic DIP PIN 1.60 (6.60).40 (6.10).045 (1.14).030 (0.76).400 (10.16).348 (8.84).070 (1.78).040 (1.0).310 (7.87).90 (7.37).00 (5.08).140 (3.56).150 (3.81).115 (.9).040 (1.0).00 (0.51).015 (0.38).008 (0.0) 3 MIN..110 (.79).090 (.9).0 (0.56).015 (0.38).400 (10.16).310 (7.87) 8-Pin SOI.157 (3.99).150 (3.81).44 (6.0).8 (5.79).050 (1.7) TYP..197 (5.00).189 (4.80).00 (0.51).013 (0.33).010 (0.5).004 (0.10).069 (1.75).053 (1.35) 8 MAX..010 (0.5).007 (0.18).050 (1.7).016 (0.40) Dimensions: inches (mm) - 9/5/ Microchip Technology Inc. DS1486A

9 WORLDWIDE SALES AND SERVIE AMERIAS orporate Office 355 West handler Blvd. handler, AZ Tel: Fax: Technical Support: Web Address: Rocky Mountain 355 West handler Blvd. handler, AZ Tel: Fax: Atlanta 500 Sugar Mill Road, Suite 00B Atlanta, GA Tel: Fax: Austin Analog Product Sales 8303 MoPac Expressway North Suite A-01 Austin, TX Tel: Fax: Boston Lan Drive, Suite 10 Westford, MA Tel: Fax: Boston Analog Product Sales Unit A-8-1 Millbrook Tarry ondominium 97 Lowell Road oncord, MA 0174 Tel: Fax: hicago 333 Pierce Road, Suite 180 Itasca, IL Tel: Fax: Dallas 4570 Westgrove Drive, Suite 160 Addison, TX Tel: Fax: Dayton Two Prestige Place, Suite 130 Miamisburg, OH 4534 Tel: Fax: Detroit Tri-Atria Office Building 355 Northwestern Highway, Suite 190 Farmington Hills, MI Tel: Fax: Los Angeles 1801 Von Karman, Suite 1090 Irvine, A 961 Tel: Fax: Mountain View Analog Product Sales 1300 Terra Bella Avenue Mountain View, A Tel: Fax: New York 150 Motor Parkway, Suite 0 Hauppauge, NY Tel: Fax: San Jose Microchip Technology Inc. 107 North First Street, Suite 590 San Jose, A Tel: Fax: Toronto 685 Northam Drive, Suite 108 Mississauga, Ontario L4V 1X5, anada Tel: Fax: ASIA/PAIFI hina - Beijing Microchip Technology Beijing Office Unit 915 New hina Hong Kong Manhattan Bldg. No. 6 haoyangmen Beidajie Beijing, 10007, No. hina Tel: Fax: hina - Shanghai Microchip Technology Shanghai Office Room 701, Bldg. B Far East International Plaza No. 317 Xian Xia Road Shanghai, Tel: Fax: Hong Kong Microchip Asia Pacific RM 101, Tower, Metroplaza 3 Hing Fong Road Kwai Fong, N.T., Hong Kong Tel: Fax: India Microchip Technology Inc. India Liaison Office Divyasree hambers 1 Floor, Wing A (A3/A4) No. 11, OíShaugnessey Road Bangalore, , India Tel: Fax: Japan Microchip Technology Intl. Inc. Benex S-1 6F , Shinyokohama Kohoku-Ku, Yokohama-shi Kanagawa, -0033, Japan Tel: Fax: Korea Microchip Technology Korea 168-1, Youngbo Bldg. 3 Floor Samsung-Dong, Kangnam-Ku Seoul, Korea Tel: Fax: ASIA/PAIFI (continued) Singapore Microchip Technology Singapore Pte Ltd. 00 Middle Road #07-0 Prime entre Singapore, Tel: Fax: Taiwan Microchip Technology Taiwan 11F-3, No. 07 Tung Hua North Road Taipei, 105, Taiwan Tel: Fax: EUROPE Australia Microchip Technology Australia Pty Ltd Suite, 41 Rawson Street Epping 11, NSW Australia Tel: Fax: Denmark Microchip Technology Denmark ApS Regus Business entre Lautrup hoj 1-3 Ballerup DK-750 Denmark Tel: Fax: France Arizona Microchip Technology SARL Parc díactivite du Moulin de Massy 43 Rue du Saule Trapu Batiment A - ler Etage Massy, France Tel: Fax: Germany Arizona Microchip Technology GmbH Gustav-Heinemann Ring 15 D Munich, Germany Tel: Fax: Germany Analog Product Sales Lochhamer Strasse 13 D-815 Martinsried, Germany Tel: Fax: Italy Arizona Microchip Technology SRL entro Direzionale olleoni Palazzo Taurus 1 V. Le olleoni Agrate Brianza Milan, Italy Tel: Fax: United Kingdom Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: Fax: All rights reserved. 001 Microchip Technology Incorporated. Printed in the USA. 1/01 Printed on recycled paper. Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchipís products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, except as maybe explicitly expressed herein, under any intellectual property rights. The Microchip logo and name are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. All rights reserved. All other trademarks mentioned herein are the property of their respective companies. 01/09/ Microchip Technology Inc. DS1486A 9-9/5/96

TC1225 TC1226 TC1227. Inverting Dual ( V IN, 2V IN ) Charge Pump Voltage Converters FEATURES GENERAL DESCRIPTION TYPICAL APPLICATIONS

TC1225 TC1226 TC1227. Inverting Dual ( V IN, 2V IN ) Charge Pump Voltage Converters FEATURES GENERAL DESCRIPTION TYPICAL APPLICATIONS Inverting Dual (, 2 ) FEATURES Small 8-Pin MSOP Package Operates from 1.8V to 5.5V Up to 5mA Output Current at Pin Up to 1mA Output Current at 2 Pin and 2 Outputs Available Low Supply Current... 120µA