FEATURES DESCRIPTIO APPLICATIO S. LT1026 Voltage Converter TYPICAL APPLICATIO

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1 LT Voltage Converter FEATRES Generates and from Single Input p to ±V Output Only Needs Four Capacitors No Inductors ma Output Current Minimum Operates Down to V No Latchup -Pin Minidip APPLICATIO S Line Drivers Op Amp Suppliers Battery Splitters RS Power DESCRIPTIO The LT is a switched capacitor voltage doubler and inverter on a single monolithic die. Capable of operating from a V to V input, it provides ±V to ±V output. Output currents of over ma are available. Two charge pumps first double the input voltage then invert the doubled voltage. Manufactured in bipolar technology, the LT is not susceptible to latchup and generates up to V. The LT offers a convenient way of generating additional system voltages without using inductors. Powering interface circuits, op amps or data acquisition circuitry off logic supplies is simplified., LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATIO Voltage Doubler and Inverter Output Voltage C C = = V T A = C C C C C LT V OT C V OT OTPT VOLTAGE (V) TA LOAD CRRENT (ma) LT TA fb

2 LT ABSOLTE IMM RATINGS W W W Supply Voltage... V V... V V... V Short-Circuit Duration... sec PACKAGE/ORDER INFORMATION W (Note ) Operating Temperature Range LTC... C to C LTI... C to C LTM (OBSOLETE)... C to C Lead Temperature (Soldering, sec)... C C C TOP VIEW V OT C C H PACKAGE -LEAD TO- METAL CAN T J = C, θ JA = C/W C C C TOP VIEW J PACKAGE -LEAD CERDIP V OT C T J = C, θ JA = C/W C C C N PACKAGE -LEAD PDIP TOP VIEW V OT C S PACKAGE -LEAD PLASTIC SO T J = C, θ JA = C/W (N) T J = C, θ JA = C/W (S) ORDER PART NMBER ORDER PART NMBER LTCH LTCJ LTMH LTMJ OBSOLETE PACKAGES Consider the N or S Packages for Alternate Source Consult LTC Marketing for parts specified with wider operating temperature ranges. ORDER PART NMBER LTCN LTCS LTIS S PART MARKING I ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T A = C. PARAMETERS CONDITIONS TYP NITS Output Voltage = V I L = ma Positive. V (Note ) I L = ma Negative. V I L = ma Positive.. V I L = ma Negative. V = V I L = ma Positive. V I L = ma Negative.. V = V I L = ma Positive. V I L = ma Negative. V I L = ma Positive. V I L = ma Negative. V I L = ma Positive. V I L = ma Negative.. V = V I L = ma, ma Positive.. V Negative.. V = V I L = ma, ma Positive. V Negative.. V fb

3 ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T A = C. LT PARAMETERS CONDITIONS TYP NITS Supply Current = V I L = ma. ma = V I L = ma ma Note : Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note : min =. for T A C TYPICAL PERFORMANCE CHARACTERISTICS W OTPT VOLTAGE (V) Load Regulation (Both Outputs Loaded) C = = V T A = C LOAD CRRENT (ma) LT TPC OTPT VOLTAGE (V) Load Regulation for Positive Loading I L = LOAD CRRENT (ma) C = = V T A = C LT TPC OTPT VOLTAGE (V) Load Regulation for Negative Loading I L = C = = V T A = C LOAD CRRENT (ma) LT TPC SPPLY CRRENT (ma) 9 Supply Current C = µf = V T A = C BOTH OTPTS LOADED SPPLY CRRENT (ma) Supply Current C = µf = V T A = C NEGATIVE OTPT LOADED SPPLY CRRENT (ma) Supply Current C = µf = V T A = C POSITIVE OTPT LOADED OTPT CRRENT (ma) OTPT CRRENT (ma) OTPT CRRENT (ma) LT TPC LT TPC LT TPC fb

4 LT TYPICAL PERFORMANCE CHARACTERISTICS W RIPPLE (mv P-P ). Ripple = V I L = mv BOTH OTPTS.. OTPT CAPACITOR (µf) TPC OTPT VOLTAGE (V) Output Voltage vs Temperature C = µf = V I L = ma TEMPERATRE ( C) LT TPC APPLICATIONS INFORMATION W The LT is a nonregulating voltage converter that converts a single input voltage into both a positive and negative output at up to ma. A positive input voltage is first doubled and then the doubled voltage is inverted. The voltage output level is dependent on both the input voltage and the output loading. The total output current available depends on the individual loading of the outputs since loading on one output affects the load and the voltage of the other. Only four external components are needed for operation. Two charge pump capacitors and two output storage capacitors. Nominal value for these capacitors is, but the LT will operate (with reduced performance) down to.. Higher value capacitors (µf) will reduce ripple and slightly lower output impedance. For higher output currents the outputs of several converters may be paralleled with common output capacitors. The substrate diodes are an inherent part of the IC, and must always be reversed biased to isolate the individual transistors. In the LT the substrate is tied to the negative output. If the negative output is not used, such as when only the voltage doubler output is needed, must be tied to ground so the substrate diodes are properly biased. The substrate diodes must never become forward biased even during overload conditions. For example, pulling positive with respect to ground can forward bias the substrate diodes. Clamping the substrate to ground with an external diode would be needed to ensure proper operation and prevent the substrate from carrying any current. No overload protection is included on the LT. Neither output is damaged by momentary shorts, but during sustained shorts the resulting high current flow will overheat the IC. fb

5 LT TYPICAL APPLICATIONS Positive to Negative Converter Voltage Doubler NC C V OT NC C LT C C TA C V OT C C LT C V OT TA Standard Configuration Voltage Doubler and Inverter Voltage Quadrupler C C C C V OT C C LT C V OT C C V OT C C LT C (FLOATING) V OT TA TA Parallel Converters for Higher Output Current and Lower Output Impedance C C C C C C V OT C LT C C C C V OT C LT V OT TA fb

6 LT TYPICAL APPLICATIONS V Powered RS Line Driver C C V OT C C LT C LT LOGIC LINE TA PACKAGE DESCRIPTION H Package -Lead TO- Metal Can (. Inch PCD) (Reference LTC DWG # --) SEATING PLANE..* (..).. (.9 9.9) DIA.. (..9). (.). (.).. (.9.99)..** (..) GAGE PLANE * LEAD DIAMETER IS NCONTROLLED BETWEEN THE REFERENCE PLANE AND THE SEATING PLANE.. ** FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS (..) REFERENCE PLANE.. (. 9.) TYP.. (..).. (.9.) INSLATING STANDOFF.. (..) PIN. (.) TYP H (TO-). PCD OBSOLETE PACKAGE fb

7 LT PACKAGE DESCRIPTION J Package -Lead CERDIP (Narrow. Inch, Hermetic) (Reference LTC DWG # --). BSC (. BSC) CORNER LEADS OPTION ( PLCS). (.). (.). (.).. (..).. (..) FLL LEAD OPTION NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS.. (..) HALF LEAD OPTION.. (..).. (..).. (..). (.) BSC... (.) RAD TYP.. (..) J OBSOLETE PACKAGE N Package -Lead PDIP (Narrow. Inch) (Reference LTC DWG # --).. (..).. (..). ±. (. ±.).* (.).. (..) ( ). (.) TYP. (.) BSC NOTE: INCHES. DIMENSIONS ARE MILLIMETERS *THESE DIMENSIONS DO NOT INCLDE MOLD FLASH OR PROTRSIONS. MOLD FLASH OR PROTRSIONS SHALL NOT EXCEED. INCH (.mm). (.). ±. (. ±.). (.). ±.* (. ±.) N.. (..).. (..) TYP..9 (..)....9 (..) (..) NOTE: INCHES TYP. DIMENSIONS IN (MILLIMETERS). DRAWING NOT TO SCALE. THESE DIMENSIONS DO NOT INCLDE MOLD FLASH OR PROTRSIONS. MOLD FLASH OR PROTRSIONS SHALL NOT EXCEED." (.mm) S Package -Lead Plastic Small Outline (Narrow.) (LTC DWG # --).. (..). (.) BSC.. (.9.9).9.9 (..) NOTE.. (..9) NOTE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights... ±. TYP. BSC SO. ±.. ±. RECOMMENDED SOLDER PAD LAYOT fb

8 LT C Regulated Converter C TYPICAL APPLICATION C V OT C C LT C V V OT 9 INPT OT LT COMP/PNP FB k. V µf INPT REFOT COMP/NPN k. M k k µf V REG ma TA9 N9 k RELATED PARTS PART NMBER DESCRIPTION COMMENTS LT Switched Capacitor Voltage Converter Can be sed as Inverter/Doubler/Divider or a Multiplier, =.V to 9V, I Q = µa, SO- LT/LTL Switched Capacitors Voltage Converters with Regulator I OT to ma/ma, =.V to V, Inverter, Neg/Pos Doubler LTC- Micropower, Regulated V In SOT- ltralow Power: I CC = µa Typical, Small -Pin SOT- LTC/LTC Low Noise, Switched Capacitor Regulator Voltage Inverter < mvp-p Typical Output Ripple, 9kHz, I OT = ma LTC/LTC SIM Power Supply and Level Translator Step-p/Step-Down Generates V, Input Voltage Range:.V to V, > kv ESD, Short-Circuit and Overtemp Protection LT/TP REV B K PRINTED IN SA Linear Technology Corporation McCarthy Blvd., Milpitas, CA 9- ()-9 FAX: () - LINEAR TECHNOLOGY CORPORATION 9 fb