UNISONIC TECHNOLOGIES CO., LTD LMV393 LINEAR INTEGRATED CIRCUIT DUAL GENERAL PURPOSE, LOW VOLAGE, COMPARATORS DESCRIPTION The UTC LMV393 is a low voltage (2.7-5V) version of the dual comparators. Its noise performance has been improved by using bipolar differential input and output stages. These comparators also have a unique characteristic in that the input common-mode voltage range includes ground even though operated from a single power supply voltage. The UTC LMV393 is designed for applications in consumer automotive, mobile communications, notebooks and PDA’s, battery powered electronics, General Purpose Portable Device, General Purpose Low Voltage Applications. FEATURES *Pb-free plating product number: LMV393L * High precision comparator. * Low operating voltage 2.7-5V. * Low Supply Current 100μA/Channel (Typical). * Low Input Bias Current 100nA (Typical). * Low Input Offset Current 2nA (Typical). * Input Common Mode Voltage Range Includes Ground. * Low Output Saturation Voltage 0.2V. ORDERING INFORMATION Ordering Number Normal Lead Free Plating LMV393-D08-T LMV393L-D08-T LMV393-S08-R LMV393L-S08-R LMV393-S08-T LMV393L-S08-T LMV393-SM1-R LMV393L-SM1-R LMV393-SM1-T LMV393L-SM1-T www.unisonic.com.tw Copyright © 2005 Unisonic Technologies Co., Ltd Package Packing DIP-8 SOP-8 SOP-8 MSOP-8 MSOP-8 Tube Tape Reel Tube Tape Reel Tube 1 of 11 QW-R104-004,A LMV393 PIN CONFIGUREATION BLOCK DIAGRAM UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw LINEAR INTEGRATED CIRCUIT 2 of 11 QW-R104-004,A LMV393 LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATINGS PARAMETER SYMBOL RATINGS UNIT Supply Voltage VCC 2.7 ~ 5.0 V Differential Input Voltage VIN(DIFF) ±VCC V Voltage on any pin (referred to V- pin) 5.5 V Junction Temperature TJ +150 °C Operating Temperature TOPR -40 ~ +85 °C Storage Temperature TSTG -65 ~ +150 °C Note Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. THERMAL CHARACTERISTICS PARAMETER SYMBOL MSOP-8 DIP-8 SOP-8 Thermal Resistance Junction to Ambient UNIT ℃/W DC ELECTRICAL CHARACTERISTICS (TJ=25℃, V-=0V, unless otherwise specified.) PARAMETER Input Offset Voltage Input Offset Voltage Average Drift Input Bias Current Input Offset Current Input Voltage Range Output Sink Current SYMBOL VIN(OFF) II(OFF) II(BIAS) II(OFF) TEST CONDITIONS MIN VIN Supply Current Voltage Gain Saturation Voltage ICC GV VSAT 2.7V 5.0V Output Leakage Current θJA RATINGS 190 100 150 ISINK 20 ISINK ≤4mA VOUT ≤1.5V 5 10 ILEAK TYP 1.7 5 100 2 -0.1 4.2 100 50 200 40 50 0.003 MAX UNIT 7 mV μV/℃ 250 nA 50 nA V 200 400 μA V/mV mV mA 1 μA AC ELECTRICAL CHARACTERISTICS (TJ=25℃, RL=5.1kΩ, V-=0V, unless otherwise specified.) PARAMETER Propagation Delay (High to Low) Propagation Delay (Low to High) SYMBOL 2.7V 5.0V 2.7V 5.0V 2.7V 5.0V 2.7V 5.0V TEST CONDITIONS Input Overdrive=10mV tPHL Input Overdrive=100mV Input Overdrive=10mV tPLH Input Overdrive=100mV UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN TYP 9 8 3.8 3.4 2 3 0.7 0.8 MAX UNIT us us 3 of 11 QW-R104-004,A LMV393 LINEAR INTEGRATED CIRCUIT APPLICATION CIRCUITS Basic Comparator A basic comparator circuit can convert analog signals to a digital output. The UTC LMV393 needs a pull-up resistor connected to the positive supply voltage which can make output switch properly. So that when the internal output transistor is off, the output voltage will be pulled up to the external positive voltage. The resister should be chosen properly. The higher resister can reduce the power dissipation. the lower resister can improve the capacity of loading output. The range of resister should between 1k to 10kΩ. The Output voltage of the comparator will be high if the input voltage at the non-inverting pin is greater than the reference voltage at the inverting pin. On the other hand it will be low. Comparator with Hysteresis The comparator may oscillate or produce a noisy output if the applied differential input voltage is near the comparator’s offset voltage, especially when the input signal is moving slowly across the comparator’s switching threshold. Addition of hysteresis or positive feedback can solve this problem. Inverting Comparator with Hysteresis It requires a three resistor network that is referenced to the supply voltage VCC of the comparator. When the output voltage is high, these resistors can be represented as R1 // R3 in series with R2. The lower set input voltage is defined as: UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 11 QW-R104-004,A LMV393 LINEAR INTEGRATED CIRCUIT APPLICATION CIRCUITS(Cont.) When VIN > Va the output voltage is low close to ground. It can be presented as R2 // R3 in series with R1. The upper trip voltage Va2 is defined as The total hysteresis provided by the network is defined as: To assure that the comparator will always switch correctly, the resistors values should be chosen as follow: RPULL-UP << RLOAD and R1 > RPULL-UP. Non-Inverting Comparator with Hysteresis It requires a two resistor network to implement a non inverting comparator with hysteresis and with a voltage reference at the inverting input. So when VIN is low, the output is also low. If the output will switch from low to high, VIN must rise up to VIN1, and VIN1 can be calculated by: When VIN is high, the output is also high, in order to make the comparator switch back to low, VIN can be calculated by: The hysteresis of this circuit is the difference between VIN1 and VIN 2. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 5 of 11 QW-R104-004,A LMV393 LINEAR INTEGRATED CIRCUIT APPLICATION CIRCUITS(Cont.) Square Wave Oscillator Comparators are suitable for oscillator applications. This application uses the minimum number of external components. The output frequency is set by the RC time constant which is determined by capacitor C1 and the resistor in the negative feedback R4 of the comparator. Capacitive load at the output would degrade the output slew rate and limit the maximum operating frequency. V R4 100k C1 75pF V + R1 100k -Vcc 4.3k V 0 - Vc + + Vc1 Va2 VOUT + Va Va1 t=0 R3 100k R2 100k T VOUT 0 Squarewave Oscillator At first, assume that the output is high, so the voltage at the inverting input VC is less than the voltage at the non-inverting input Va, the capacitor C1 has to be discharged. When it has charged up to value equal to the positive input voltage Va1, the comparator output will switch. Va1 will be given by: If: R1=R2=R3 Then: When the output switches to ground, the value of Va is reset by the resistor network: Then capacitor C1 discharge through a resistor towards ground. The output will return to its high state when the voltage across the capacitor has discharged to a value equal to Va2.The time to charge the capacitor can be calculated from: Where VMAX =2VCC/3 and VC = VCC/3 One period will be given by: 1/freq = 2t or calculating the exponential gives: 1/freq = 2(0.694) R4 C1Resistors R3 and R4 must be at least two times larger than R5 to insure a reasonable VO. The frequency stability of this circuit should strictly be a function of the external components. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 6 of 11 QW-R104-004,A LMV393 LINEAR INTEGRATED CIRCUIT APPLICATION CIRCUITS(Cont.) Free Running Multivibrator This oscillator circuit can generate a train of stable clock for precise timekeeping applications. We can obtain it by using a resonator as the feedback component. A quartz crystal in its series-resonant mode can make the circuit oscillating well. For the comparator be switching symmetrically about +VCC/2, the value of R1 and R2 must choose equal. The RC time constant of R3 and C1 is set to be several times greater than the period of the oscillating frequency. When choose crystal, be sure to order series resonant with desired temperature coefficient. Pulse generator with variable duty cycle: A pulse generator with variable duty cycle can be obtained by creating two separated paths for C1 charge and discharge into the basic square wave generator. One path, through R2 and D2 will charge the capacitor and set the pulse width (t1). The other path, R1 and D1 will discharge the capacitor and set the time between pulses (t2). Varying resistor R1, R2 can alter the time between pulses and the pulse width. Both controls also change the frequency of the generator. The pulse width and time between pulses can be found from: V1 = Vmax (1 − e − t1 V1 = Vmax e R4C1 − t2 R5C1 ) Rise time Fall time Where Vmax = 2VCC 3 And V1 = Vmax VCC = 3 3 then 1 = e − t1 2 R4C1 t2 is then given by: 1 = e − t2 2 R5C1 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 7 of 11 QW-R104-004,A LMV393 LINEAR INTEGRATED CIRCUIT APPLICATION CIRCUITS(Cont.) V R1 1M D1 R2 100k D2 + 15k * C1 80pF + - 6μs tot1 V+ R5 1M -V 60μs t2 0 VOUT + R3 1M R4 1M *FOR LARGE RATIOS OF R1/R2. D1 CAN BE OMITTED. Pulse Generator At last, we get, t1 = R4C1 ln 2 t2 = R5C1 ln 2 These terms have a slight error because Vmax is not exactly equal to 2/3 VCC but is actually reduced by the diode drop to: Vmax = 2 (VCC − VBE ) 3 1 = e − t1 R4C1 2(1 − VBE ) 1 = e − t2 R5C1 2(1 − VBE ) And that’s the exact value we get. t1 = R4C1 ln 2(1 − VBE ) t2 = R5C1 ln 2(1 − VBE ) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 8 of 11 QW-R104-004,A LMV393 LINEAR INTEGRATED CIRCUIT APPLICATION CIRCUITS(Cont.) Positive Peak Detector: Positive peak detector is basically the comparator operated as a unit gain follower with a large holding capacitor from the output to ground. Additional transistor is added to the output to provide a low impedance current source. When the output of the comparator goes high, current is passed through the transistor to charge up the capacitor. The only discharge path will be the 1M ohm resistor shunting C1 and any load that is connected to the output. The decay time can be altered simply by changing the 1MΩ resistor. The output should be used through a high impedance follower to a avoid loading the output of the peak detector. Negative Peak Detector: For the negative detector, the output transistor of the comparator acts as a low impedance current sink. The only discharge path will be the 1MΩ resistor and any load impedance used. Decay time is changed by varying the 1MΩ resistor. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 9 of 11 QW-R104-004,A LMV393 TYPICAL CHARACTERISTICS Output Voltage vs Output Current at 2.7 Supply 700 600 +85℃ Output Voltage (mV) Output Voltage (mV) Output Voltage vs Output Current at 5V Supply 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 +25℃ 500 +85℃ 400 +25℃ 300 200 100 0 0 10 20 40 30 50 0 5 Output Current (mA) VIN=0V 20 5 Output Voltage VOUT (V) 200 +25℃ Input Bias Current (nA) 15 10 Output Current (mA) Response Time vs Input Overdrives Negative Transition Input Bias Current vs Supply Voltage 250 150 +85℃ 100 100mV 4 10mV 20m V 3 2 Vcc=5V Ta=25℃ RL=5.1kΩ 1 0 ~ ~ Input Voltage VIN (mV) 50 ~ ~ 100 5 0 2.5 0 Overdrive 5.5 4.5 3.5 Supply Voltage (V) 0 Response Time for Input Overdrive Positive Transition 3 100mV 3 20mV 5mV 2 1 0 0.5 1.5 1 Time (μs) 2 2.5 3 Response Time vs Input Overdrives Negative Transition 100m V 2 10mV 20mV 1 Vcc=2.7V Ta=25℃ RL=5.1kΩ 0 ~ ~ ~ ~ Overdrive Input Voltage VIN (mV) Output Voltage VOUT (V) 4 Output Voltage VOUT (V) Vcc=5V Ta=25℃ RL=5.1kΩ 5 Input Voltage (mV) LINEAR INTEGRATED CIRCUIT 0 ~ ~ ~ ~ 100 -100 0 3 6 Time (μs) 9 12 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 0 Overdrive 0 0.5 1. 1 5 Time (μs) 2 10 of 11 QW-R104-004,A LMV393 TYPICAL CHARACTERISTICS (Cont.) Input Voltage (mV) Output Voltage VOUT (V) LINEAR INTEGRATED CIRCUIT UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 11 of 11 QW-R104-004,A