LF111/LF211/LF311 Voltage Comparators General Description The LF111, LF211 and LF311 are FET input voltage comparators that virtually eliminate input current errors. Designed to operate over a 5.0V to g 15V range the LF111 can be used in the most critical applications. The extremely low input currents of the LF111 allows the use of a simple comparator in applications usually requiring input current buffering. Leakage testing, long time delay circuits, charge measurements, and high source impedance voltage comparisons are easily done. Further, the LF111 can be used in place of the LM111 eliminating errors due to input currents. See the ‘‘application hints’’ of the LM311 for application help. Features Y Y Y Eliminates input current errors Interchangeable with LM111 No need for input current buffering Schematic Diagram Note: Do Not Ground Strobe Pin or Balance/Strobe Pin. See Note 7. Connection Diagram TL/H/5703 – 2 Metal Can Package TL/H/5703 – 1 Top View Order Number LF111H, LF111H-MIL or LF311H See NS Package Number H08C C1995 National Semiconductor Corporation TL/H/5703 RRD-B30M115/Printed in U. S. A. LF111/LF211/LF311 Voltage Comparators November 1994 Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications. LF111/LF211 Operating Temp. Range LF111 LF211 LF311 (Note 8) Total Supply Voltage (V84) Output to Negative Supply Voltage (V74) Ground to Negative Supply Voltage (V14) Differential Input Voltage Input Voltage (Note 1) Power Dissipation (Note 2) Output Short Circuit Duration LF111/LF211 36V LF311 36V 50V b 55§ C to a 125§ C b 25§ C to a 85§ C 0§ C to a 70§ C 40V Storage Temp. Range Lead Temp. (Soldering, 10 seconds) ESD rating to be determined. 30V 30V g 30V g 30V g 15V g 15V 500 mW 10 seconds 500 mW 10 seconds LF311 b 65§ C to a 150§ C b 65§ C to a 150§ C 260§ C 260§ C Electrical Characteristics (LF111/LF211) (Note 3) Typ Max Units Input Offset Voltage (Note 4) Parameter TA e 25§ C, RS s 50k Conditions Min 0.7 4.0 mV Input Offset Current (Note 4) TA e 25§ C, VCM e 0 (Note 6) 5.0 25 pA Input Bias Current TA e 25§ C, VCM e 0 (Note 6) 20 50 pA Voltage Gain TA e 25§ C Response Time (Note 5) TA e 25§ C 200 Saturation Voltage VINs b5.0 mV, IOUT e 50 mA, TA e 25§ C 0.75 Strobe On Current TA e 25§ C 3.0 Output Leakage Current VINs5.0 mV, VOUT e 35V, TA e 25§ C 0.2 Input Offset Voltage (Note 4) RS s 50k 40 200 V/mV ns 1.5 V mA 10 nA 6.0 mV Input Offset Current (Note 4) VS e g 15V, VCM e 0 (Note 6) 2.0 3.0 nA Input Bias Current VS e g 15V, VCM e 0 (Note 6) 5.0 7.0 nA g 14 b 13.5 Input Voltage Range 13.0 V Saturation Voltage V a t4.5V, Vb e 0 VINs b6.0 mV, IOUTs8.0 mA 0.23 0.4 V Output Leakage Current VINt5.0 mV, VOUT e 35V 0.1 0.5 mA Positive Supply Current TA e 25§ C 5.1 6.0 mA Negative Supply Current TA e 25§ C 4.1 5.0 mA Note 1: This rating applies for g 15V supplies. The positive input voltage limit is 30V above the negative supply. The negative input voltage limit is equal to the negative supply voltage or 30V below the positive supply, whichever is less. Note 2: The maximum junction temperature of the LF111 is a 150§ C, the LF211 is a 110§ C and the LF311 is a 85§ C. For operating at elevated temperatures, devices in the H08 package must be derated based on a thermal resistance of a 65§ C/W junction to ambient (in 400 linear feet/min air flow), a 165§ C/W junction to ambient (in static air), or a 20§ C/W junction to case. Note 3: These specifications apply for VS e g 15V, and the Ground pin at ground, and b 55§ C s TA s a 125§ C for the LF111, unless otherwise stated. With the LF211, however, all temperature specifications are limited to b 25§ C s TA s g 85§ C and for the LF311 0§ C s TA s a 70§ C. The offset voltage, offset current and bias current specifications apply for any supply voltage from a single 5.0V supply up to g 15V supplies. Note 4: The offset voltages and offset currents given are the maximum values required to drive the output within a volt of either supply with a 1.0 mA load. Thus, these parameters define an error band and take into account the worst case effects of voltage gain and input impedance. Note 5: The response time specified (see definitions) is for a 100 mV input step with 5.0 mV overdrive. Note 6: For input voltages greater than 15V above the negative supply the bias and offset currents will increaseÐsee typical performance curves. Note 7: This specification gives the current that must be drawn from the strobe pin to ensure the output is properly disabled. Do not short the strobe pin to ground; it should be current driven at 3 to 5 mA. Note 8: Refer to RETSF111X for LF111H military specifications. 2 Electrical Characteristics (LF311) (Note 3) Typ Max Units Input Offset Voltage (Note 4) Parameter TA e 25§ C, RSs50k Conditions Min 2.0 10 mV Input Offset Current (Note 4) TA e 25§ C, VCM e 0 (Note 6) 5.0 75 pA Input Bias Current TA e 25§ C, VCM e 0 (Note 6) 25 150 Voltage Gain TA e 25§ C 200 Response Time (Note 5) TA e 25§ C 200 Saturation Voltage VINs b10 mV, IOUT e 50 mA, TA e 25§ C 0.75 Strobe On Current TA e 25§ C 3.0 Output Leakage Current VINt10mV, VOUT e 35V, TA e 25§ C 0.2 Input Offset Voltage (Note 4) RSs50k Input Offset Current (Note 4) VS e g 15V, VCM e 0 (Note 6) 1.0 nA Input Bias Current VS e 15V, VCM e 0 (Note 6) 3.0 nA a 14 b 13.5 V V Input Voltage Range pA V/mV ns 1.5 V mA 10 nA 15 mV Saturation Voltage V a t4.5V, Vb e 0 VINs b10 mV, IOUTs8.0 mA 0.23 0.4 V Positive Supply Current TA e 25§ C 5.1 7.5 mA Negative Supply Current TA e 25§ C 4.1 5.0 mA Note 1: This rating applies for g 15V supplies. The positive input voltage limit is 30V above the negative supply. The negative input voltage limit is equal to the negative supply voltage or 30V below the positive supply, whichever is less. Note 2: The maximum junction temperature of the LF111 is a 150§ C, the LF211 is a 110§ C and the LF311 is a 85§ C. For operating at elevated temperatures, devices in the H08 package must be derated based on a thermal resistance of a 165§ C/W, junction to ambient, or a 20§ C/W, junction to case. Note 3: These specifications apply for VS e g 15V and b 55§ C s TA s a 125§ C for the LF111, unless otherwise stated. With the LF211, however, all temperature specifications are limited to b 25§ C s TA s a 85§ C and for the LF311 0§ C s TA s a 70§ C. The offset voltage, offset current and bias current specifications apply for any supply voltage from a single 5.0 mV supply up to g 15V supplies. Note 4: The offset voltages and offset currents given are the maximum values required to drive the output within a volt of either supply with a 1.0 mA load. Thus, these parameters define an error band and take into account the worst case effects of voltage gain and input impedance. Note 5: The response time specified (see definitions) is for a 100 mV input step with 5.0 mV overdrive. Note 6: For input voltages greater than 15V above the negative supply the bias and offset currents will increaseÐsee typical performance curves. Note 7: This specification gives the current that must be drawn from the strobe pin to ensure the output is properly disabled. Do not short the strobe pin to ground; it should be current driven at 3 to 5 mA. Auxiliary Circuits Offset Balancing Strobing Increasing Input Stage Current* TL/H/5703 – 15 *Increases typical common mode slew from 7.0V/ms to 18V/ms TL/H/5703–13 TL/H/5703 – 14 Note: Do Not Ground Strobe Pin. 3 Typical Performance Characteristics Input Bias Current vs Common Mode Input Bias Current vs Temperature Transfer Function Response Time for Various Input Overdrives Response Time for Various Input Overdrives Output Saturation Voltage Response Time for Various Input Overdrives Response Time for Various Input Overdrives Supply Current Output Limiting Characteristics Supply Current Leakage Currents TL/H/5703 – 4 4 Typical Applications 100 kHz Free Running Multivibrator Crystal Oscillator TL/H/5703 – 7 *TTL or DTL fanout of two. TL/H/5703 – 3 10 Hz to 10 kHz Voltage Controlled Oscillator *Adjust for symmetrical squarewave time when VIN e 5.0 mV. ² Minimum capacitance 20 pF. Maximum frequency 50 kHz. TL/H/5703 – 5 5 Typical Applications (Continued) Frequency Doubler Frequency range: InputÐ5.0 kHz to 50 kHz OutputÐ10 kHz to 100 kHz TL/H/5703 – 8 Zero Crossing Detector Driving MOS Switch Zero Crossing Detector Driving MOS Logic TL/H/5703–9 TL/H/5703 – 10 Driving Ground-Referred Load Comparator and Solenoid Driver TL/H/5703–11 *Input polarity is reversed when using pin 1 as output. TL/H/5703 – 12 6 Typical Applications (Continued) Switching Power Amplifier TL/H/5703 – 16 Switching Power Amplifier TL/H/5703 – 17 7 Typical Applications (Continued) Relay Driver with Strobe *Absorbs inductive kickback of relay and protects IC from severe voltage aa line. transients on V TL/H/5703 – 18 Note: Do Not Ground Strobe Pin. Positive Peak Detector *Solid tantalum TL/H/5703 – 19 Negative Peak Detector *Solid tantalum TL/H/5703 – 20 8 Typical Applications (Continued) TTL Interface with High Level Logic *Values shown are for a 0 to 30V logic swing and a 15V threshold. TL/H/5703 – 21 ² May be added to control speed and reduce susceptibility to noise spikes Using Clamp Diodes to Improve Response TL/H/5703 – 6 9 LF111/LF211/LF311 Voltage Comparators Physical Dimensions inches (millimeters) Metal Can Package (H) Order Number LF111H, LF111H-MIL or LF311H NS Package Number H08C LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 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Tel: 81-043-299-2309 Fax: 81-043-299-2408 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. This datasheet has been download from: www.datasheetcatalog.com Datasheets for electronics components.