APPLICATIONS TYPICAL APPLICATION. LTC1841/LTC1842/LTC1843 Ultralow Power Dual Comparators with Reference DESCRIPTION FEATURES

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1 LTC/LTC/LTC3 ltralow Power Dual Comparators with Reference FEATRES ltralow Quiescent Current: 3.µA Typ Open-Drain Outputs Typically Sink Greater Than ma Wide Supply Range: (LTC) Single: V to V Dual: ±V to ±.V Input Voltage Range Includes the Negative Supply Reference Output Drives.µF Capacitor Adjustable Hysteresis µs Propagation Delay with mv Overdrive No Current Spike When Switching APPLICATIONS Battery-Powered System Monitoring Threshold Detectors Window Comparators Oscillator Circuits, LTC and LT are registered trademarks of Linear Technology Corporation. DESCRIPTION The LTC /LTC/LTC3 are ultralow power dual comparators with built-in reference (LTC/LTC3). The comparators feature less than.µa supply current over temperature, a.v ±% reference, programmable hysteresis and open-drain outputs that sink current. The reference output can drive a bypass capacitor of up to.µf without oscillation. The LTC operates from a single V to V supply or a dual ±V to ±.V supply. The LTC/LTC3 operate from a single.v to V supply or a dual ±.V to ±.V supply. The LTC/LTC3 hysteresis is easily programmed by using two resistors and the pin. The comparators input operates from the negative supply to within.3v of the positive supply. The comparators output stage can typically sink greater than ma. By eliminating the cross-conduction current that normally happens when the comparators change logic states, power supply glitches are eliminated. The LTC/LTC/LTC3 are available in SO- packages. TYPICAL APPLICATION -CELL Li-Ion BATTERY R.M R k R3 M R k R.M 3 IN A Single Li-Ion Cell to V Supply C R L µf k µh D V CC LTC3 IN B IN SW LT3- OT B 3 SHDN I T PGND SENSE V C GND OT A R C k C C.µF C, C: SANYO OS-CON D: MOTOROLA MBRS3LT3 L: COILTRONICS CTX-3 Si99DY R k /3 TA OTPT V ma C µf LBO SPPLY CRRENT (µa) 3 T A = C LTC3 Supply Current vs Supply Voltage SPPLY VOLTAGE (V) /3 TA

2 LTC/LTC/LTC3 ABSOLTE MAXIMM RATINGS W W W (Note ) Voltage V to...v to.3v IN, IN,... (V.3V) to (.3V)... (V.3V) to (.3V) OT... V to (.3V) Current IN, IN,... ma... ma OT... ma OT Short-Circuit Duration (V.V)... Continuous Power Dissipation... mw Operating Temperature Range LTCC/LTCC/LTC3C... C to C LTCI/LTCI/LTC3I... C to C Storage Temperature Range... C to C Lead Temperature (Soldering, sec)... 3 C PACKAGE/ORDER INFORMATION W OT A IN A 3 IN A TOP VIEW S PACKAGE -LEAD PLASTIC SO OT B V IN B IN B T JMAX = C, θ JA = C/ W ORDER PART NMBER LTCCS LTCIS Consult factory for Military grade parts. S PART MARKING I OT A IN A 3 IN B TOP VIEW S PACKAGE -LEAD PLASTIC SO OT B V T JMAX = C, θ JA = C/ W ORDER PART NMBER LTCCS LTCIS S PART MARKING I OT A IN A 3 IN B TOP VIEW S PACKAGE -LEAD PLASTIC SO T JMAX = C, θ JA = C/ W ORDER PART NMBER LTC3CS LTC3IS OT B V S PART MARKING 3 3I ELECTRICAL CHARACTERISTICS V = V, = V, T A = C unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS Power Supply V Supply Voltage Range LTC. V LTC/LTC3. V I CC Supply Current = (Note ) 3.. µa Comparator V OS Comparator Input Offset Voltage (Note 3) ±3 ± mv I IN Input Leakage Current (IN, IN ) IN = IN =.V (LTC), ±. ±. na IN = IN = V (LTC/LTC3) V IN Comparator Input Voltage Range V.3V V PSRR Power Supply Rejection Ratio V = V to V (LTC),. mv/v V =.V to V (LTC/LTC3) CMRR Common Mode Rejection Ratio V CM = to (V.3V) LTC. mv/v V Hysteresis Input Voltage Range LTC/LTC3 V mv V V

3 LTC/LTC/LTC3 ELECTRICAL CHARACTERISTICS V = V, = V, T A = C unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS t PD Propagation Delay C OT = pf, R PLL-P = k Overdrive = mv µs Overdrive = mv µs I LEAK Output Leakage Current V OT = V (Note ) na V OL Output Low Voltage I OT =.ma.v V Reference (LTC/LTC3) V Reference Voltage No Load C...9 V C to C..9 V C to C.. V V Load Regulation I SORCE = ma 3 mv I SINK =µa. mv mv e n Voltage Noise Hz to khz µv RMS V = 3V, = V, T A = C unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS Power Supply V Supply Voltage Range LTC. V LTC/LTC3. V I CC Supply Current = (Note ) 3.. µa Comparator V OS Comparator Input Offset Voltage (Note 3) ±3 ± mv I IN Input Leakage Current (IN, IN ) IN = IN =.V (LTC), ±. ± na IN = IN = V (LTC/LTC3) V IN Comparator Input Voltage Range V.3V V PSRR Power Supply Rejection Ratio V = V to V (LTC ),. mv/v V =.V to V (LTC/LTC3) CMRR Common Mode Rejection Ratio V CM = to (V.3V) LTC. mv/v V Hysteresis Input Voltage Range LTC/LTC3 V mv V V t PD Propagation Delay C OT = pf, R PLL-P = k Overdrive = mv µs Overdrive = mv µs I LEAK Output Leakage Current V OT = V (Note ) na V OL Output Low Voltage I O =.ma.v V Reference (LTC/LTC3) V Reference Voltage No Load C...9 V C to C..9 V C to C.. V V Load Regulation I SORCE = ma mv I SINK =µa. mv mv e n Voltage Noise Hz to khz µv RMS The denotes specifications which apply over the full operating temperature range. Note : Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note : IN = IN mv, output is in high impedance state. Note 3: V CM = /(V ) for LTC, V CM = V for LTC/ LTC3. 3

4 LTC/LTC/LTC3 TYPICAL PERFORMANCE CHARACTERISTICS W INPT VOLTAGE (mv) OTPT VOLTAGE (V) Comparator Response Time vs Input Overdrive, with R PLL-P = k T A = C mv mv 3 mv mv RESPONSE TIME (µs) INPT VOLTAGE (mv) OTPT VOLTAGE (V) 3 Comparator Response Time vs Input Overdrive, with R PLL-P = k T A = C mv mv mv mv RESPONSE TIME (µs) SINK CRRENT (ma) Comparator Short-Circuit Sink Current vs Supply Voltage T A = C OT CONNECTED TO V ///3 G 3 9 SPPLY VOLTAGE (V) ///3 G3 RESPONSE TIME (µs) ///3 G Comparator Response Time vs Load Capacitance with mv Input Overdrive t PHL t PLH LOAD CAPACITANCE (nf) ///3 G Comparator Response Time at Low Supply Voltage. Comparator Output Voltage Low vs Load Current T A = C RESPONSE TIME (µs) mv OVERDRIVE mv OVERDRIVE OTPT VOLTAGE HIGH (V).... V = V V = 3V V = V SPPLY VOLTAGE (V) 3 LOAD CRRENT (ma) ///3 G ///3 G

5 TYPICAL PERFORMANCE CHARACTERISTICS W LTC/LTC/LTC3 POSITIVE-TO-NEGATIVE INPT VOLTAGE (mv) LTC/LTC3 Hysteresis Control OTPT HIGH OTPT LOW 3 V V (mv) ///3 G SPPLY CRRENT (µa) LTC/LTC3 Supply Current vs Temperature V = 3V = V V = V = V. TEMPERATRE ( C) V = V = V ///3 G ERENCE OTPT VOLTAGE (V) Reference Output Voltage vs Output Load Current.9 V CC = V. SORCE..... ERENCE OTPT VOLTAGE (V) Reference Output Voltage vs Output Load Current (Sink) V CC = V V CC = V SINK OTPT LOAD CRRENT (ma). 3 OTPT LOAD CRRENT (µa) //3 G9 ///3 G. Reference Voltage vs Temperature. ERENCE VOLTAGE (V) TEMPERATRE ( C) ///3 G

6 LTC/LTC/LTC3 PIN FNCTIONS OT A (Pin ): Comparator A Open-Drain Output. Output can typically sink greater than ma. (Pin ): Negative Supply. IN A (Pin 3): Noninverting Input of Comparator A. Input common mode range extends from to V.3V. Input current is typically pa at C. IN A (Pin ) (LTC): Inverting Input of Comparator A. Input common mode range extends from to V.3V. Input current is typically pa at C. IN B (Pin ) (LTC): Noninverting Input of Comparator B. Input common mode range extends from to V.3V. Input current is typically pa at C. IN B (Pin ) (LTC3): Inverting Input of Comparator B. Input common mode range extends from to V.3V. Input current is typically pa at C. IN B (Pin ) (LTC): Inverting Input of Comparator B. Input common mode range extends from to V.3V. Input current is typically pa at C. (Pin ) (LTC/LTC3): Hysteresis Input. Connect to if not used. Input voltage range is from V to V mv. IN B (Pin ) (LTC): Noninverting Input of Comparator B. Input common mode range extends from to V.3V. Input current is typically pa at C. (Pin ) (LTC/LTC3): Reference Output..V with respect to. Can typically source greater than ma and sink µa at C. Can drive.µf bypass capacitor without oscillation. V (Pin ) (LTC): Positive Supply. V to V. V (Pin ) (LTC/LTC3): Positive Supply..V to V. OT B (Pin ): Comparator B Open-Drain Output. Output can typically sink greater than ma. OT A LTC V A B 3 IN A IN B IN A OT A 3 IN A IN B OT A 3 IN A IN B A LTC A LTC3 B B OT B IN B PD OT B V PD OT B V 3 PD

7 LTC/LTC/LTC3 APPLICATIONS INFORMATION W The LTC/LTC/LTC3 are dual micropower comparators with a built-in.v reference (LTC/ LTC3). Features include programmable hysteresis, wide supply voltage range (V to V) and the ability for the reference to drive up to a.µf capacitor without oscillation. The comparators open-drain outputs can typically sink greater than ma and the supply current glitches that normally occur when switching logic states have been eliminated. Power Supplies The comparators operate from a single V to V (.V to V for LTC/LTC3) or dual ±V to ±.V supply (±.V to ±.V for LTC/LTC3). If the reference output is required to source more than ma or the supply source impedance is high, V should be bypassed with a.µf capacitor. Comparator Inputs The comparators input can swing from the negative supply to within.3v (max) of the positive supply V. The input can be forced 3mV below or above V without damage and the typical input leakage current is only ±pa. Comparator Outputs Each comparator output is an open-drain pull-down to typically capable of sinking greater than ma. The low output leakage current while in three-state mode allows a high value pull-up resistor to be used. The open-drain outputs can be wire OR-ed or used in level shifting applications. Voltage Reference The internal bandgap reference has an output voltage of.v referenced to. The reference accuracy is.% from C to C. It can typically source greater than ma and sink up to µa with a V supply. The reference can drive a bypass capacitor of up to.µf without oscillation. By inserting a series resistor, capacitance values up to µf can be used (Figure ). RESISTOR VALE (kω) Figure. Damping the Reference Output.. ERENCE OTPT R LTC3.. CAPACITOR VALE (µf) /3 F Figure. Damping Resistance vs Bypass Capacitor Value Figure 3 shows the bypassed reference output with a square wave applied to the V pin. Resistors R and R3 set a mv hysteresis voltage band while R damps the reference response. Note that the comparator output doesn t trip. C /3 F Figure shows the resistor value required for different capacitor values to achieve critical damping. Bypassing the reference can help prevent false tripping of the comparators by preventing glitches on V or reference load transients from disturbing the reference output voltage.

8 LTC/LTC/LTC3 APPLICATIONS INFORMATION W V TO V mv/div R k R3.M Figure 3a. Power Supply Transient Test Circuit V V V V R 3Ω C µf 3 IN A V V LTC3 M OT A /3 F3a OT A V R = HB I ()(I ) R LTC3 R R = ( ) V HB.V I Figure. Programmable Hysteresis /3 F %. If hysteresis is not wanted, the pin should be shorted to. Acceptable values for I range are from.µa to µa. If.M is chosen for R, then the value of R is equal to the value of V HB. Window Detector The LTC3 is ideal for use as a micropower window detector as shown in Figure. The values of R, R and R3 are selected for a.v undervoltage threshold and a.v overvoltage threshold. R and R set the hysteresis voltage. The following design procedure can be used to select the component values: OT V ms/div /3 F3b Figure 3b. Power Supply Transient Rejection V IN R3 M 3 IN A V LTC3 OT A M Hysteresis Hysteresis can be added to the LTC/LTC3 by connecting a resistor (R) between the and pins and a second resistor (R) from to (Figure ). The difference between the upper and lower threshold voltages, or hysteresis voltage band (V HB ), is equal to twice the voltage difference between the and pins. As more hysteresis is added, the upper threshold increases the same amount as the low threshold decreases. The maximum voltage allowed between and pins is mv, producing a maximum hysteresis voltage band of mv. The hysteresis band may vary by up to R.k R 9k R k R.M IN B OT B /3 F Figure. Dual Level Detector V OTH =.V V TH =.V

9 LTC/LTC/LTC3 APPLICATIONS INFORMATION W. Choose the required hysteresis voltage band and calculate values for R and R according to the formulas in the hysteresis section. In this example, ±mv of hysteresis has been added at the comparator input (V H = V HB /). Note that the hysteresis apparent at V IN will be larger because of the input resistor divider.. Select R. The leakage current into IN B is under na so the current through R should exceed na, to ensure threshold accuracy. R values up to about M can be used, but values in the k to M range are usually easier to deal with. In this example choose R = 9k. 3. Calculate R R3. The overvoltage threshold should be set at.v. The design equation is as follows: V TH R R3= R V VH. = 9k.. =. M. Calculate R. The undervoltage threshold should be set at.v. The design equation is as follows: ( ) R R R R V V H = 3 R VLTH.. = ( 9k. M) 9k. =. k Choose R =.9k (% standard value). Calculate R3: R3 = (R R3) R =.M.9k =.M Choose R3 = M (% standard value). Verify the resistor values. The equations are as follows, evaluated for the above example: Overvoltage threshold: ( ) V V V R R R 3 OTH = H R =. V ndervoltage threshold: VTH V VH R R R 3 R R =. V = ( ) where the hysteresis voltage V H R = ( V ) R 9

10 LTC/LTC/LTC3 TYPICAL APPLICATION Battery Switchover Circuit 9V WALL ADAPTER 3k -CELL BATTERY N.M 3 IN A k V LTC OT A Si933 M LTC STEP-DOWN REGLATOR M OTPT 3.3V LBO IN B OT B.µF k k.m TA

11 PACKAGE DESCRIPTION LTC/LTC/LTC3 Dimensions in inches (millimeters) unless otherwise noted. S Package -Lead Plastic Small Outline (Narrow.) (LTC DWG # --).9.9* (..).. (.9.9)..** (3. 3.9) 3.. (.3.).. (..) TYP.3.9 (.3.).. (..).... *DIMENSION DOES NOT INCLDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED." (.mm) PER SIDE ** DIMENSION DOES NOT INCLDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED." (.mm) PER SIDE..9 (.3.3). (.) TYP SO 99 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.

12 LTC/LTC/LTC3 TYPICAL APPLICATION Low-Battery Load Disconnect and Charge Termination Si99DY V IN -CELL Li-Ion BATTERY.M 3k IN B V LTC3 OT B M LBO AT V IN = 3V M.M 3 IN A OT A FLL CHARGE AT V IN =.V k.m /3 TA3 RELATED PARTS PART NMBER DESCRIPTION COMMENTS LT /LT9 Dual/Quad µa Precision Single Supply Op Amps µv Max V OS, na Max I BIAS LT3 Single µa, 3MHz, V/µs Op Amp with Shutdown C-Load TM Op Amp Stable Driving Any Capacitive Load LT3/LT33 Dual/Quad µa, 3MHz, V/µs Op Amps C-Load Op Amps Stable Driving Any Capacitive Load LTC/LTC Micropower Comparator with % Reference.V ±% Reference, ±mv (Max) Input Offset LTC/LTC Micropower Dual Comparator with % Reference.V ±% Reference (LTC) LTC3/LTC/LTC Micropower Quad Comparator with % Reference LTC3 Has.V Reference, LTC/LTC Have.V Reference and Adjustable Hysteresis LTC Low Quiescent Current High Efficiency Step-Down µa Standby Current, 9% Efficiency, Space Saving -Pin Switching Regulator MSOP Package LT9.µA Max, Dual Precision Rail-to-Rail 3µV Max V OS, pa I BIAS, pa I OS Input and Output Op Amp LT 3mA Low Dropout Regulator with Micropower.V Dropout Voltage, µa Quiescent Current, Adjustable Quiescent Current and Shutdown Output 3V, 3.3V and V Fixed LTC/LTC Micropower Op Amp, Comparator and Reference.V ±.% Reference (LTC) Op Amp Outputs Stable with pf Load LT3 Micropower Precision Shunt Voltage Reference.V Output, µa Operating Current,.% Initial Accuracy ppm/ C Max Drift C-Load is a trademark of Linear Technology Corporation. Linear Technology Corporation 3 McCarthy Blvd., Milpitas, CA 93- () 3-9 FAX: () f LT/TP 9 K PRINTED IN SA LINEAR TECHNOLOGY CORPORATION 99

FEATURES TYPICAL APPLICATIO. LTC1443/LTC1444/LTC1445 Ultralow Power Quad Comparators with Reference DESCRIPTIO APPLICATIO S

FEATURES TYPICAL APPLICATIO. LTC1443/LTC1444/LTC1445 Ultralow Power Quad Comparators with Reference DESCRIPTIO APPLICATIO S LTC/LTC/LTC ltralow Power Quad Comparators with Reference FEATRES ltralow Quiescent Current:.µA Max Reference Output Drives.µF Capacitor Adjustable Hysteresis (LTC/LTC) Wide Supply Range Single: V to V