TIGER ELECTRONIC CO.,LTD LM2904N/D LOW POWER DUAL OPERATIONAL AMPLIFIER LM2904 DESCRIPTION Outline Drawing The LM2904 consists of two independent, high gain, internally frequency compensated operational amplifiers which were designed specifically to operate from a single power supply over a wide range of voltages. Operation from split power supplies is also possible and the low power supply current drain is independent of the magnitude of the power supply LM2904N voltage. Application areas include transducer amp lifiers, DIP-8 DC gain blocks and all the conventional op amp circuits which now can be more easily implemented in single power supply systems. For example, the LM2904 can be directly operated off of the standard LM2904D +5V power supply voltage which is used in digital systems and will easily provide the required interface electronics without requiring the additional ±1 5V power su p p lies. SOP-8 UNIQUE CHARACTERISTICS In the linear mode the input common-mode voltage range includes ground and the output voltage can also swing to ground, even though operated from only a single power supply voltage. The unity gain cross frequency is temp erature comp ensated. The input bias current is also temp erature comp ensated. ADVANTAGES Two internally comp ensated op amps. Eliminates need for dual supplies. Allows direct sensing near GND and V O U T also goes to GND. Comp atible with all forms of logic. Power drain suitable for battery operation. 1/8 LM2904N/D FEATURES Internally frequency compensated for unity gain Large dc voltage gain: 100 dB Wide bandwidth (unity gain): 1 MHz (temperature comp ensated) Wide power supply range: — Single supply: 3V to 32V — or dual supplies: ±1.5V to ±16V Very low supply current drain (500 µA)—essentially independent of supply voltage. Low input offset voltage: 2 mV Input common-mode voltage range includes ground Differential input voltage range equal to the power supply voltage Large output voltage swing: 0V to V+- 1.5V BLOCK DIAGRAM AND PIN CONNECTION 8 V+ OUTPUT A 1 INVERTING INPUT A 2 NON-INVERTING INPUT A 3 GND 7 OUTPUT B A - + B + - 6 INVERTING INPUT B 5 NON-INVERTING INPUT B 4 ABSOLUTE MAXIMUM RATINGS (Ta=25 °C) Characteristic Supply Voltage,V + Differential Input Voltage Input Vo ltage Power Dissipation (Note 1) Value Unit 3 2 或 ±1 6 V 32 V -0.3~32 V DIP Package 550 SOP Package 530 Output Short-Circuit to GND（ One Amplifier）（ Note 2） （ V + ≤15V、 Ta=2 5℃ ） mW Continuous 50 mA Operating Temp erature Range -20~+85 ℃ Storage Temp erature Range -65~150 ℃ Input Current （ V I N <-0.3V） (Note 3) 2/8 LM2904N/D ELECTRICAL CHARACTERISTICS Parameter (Unless otherwise specified: V + =5.0V) Test Conditions Input Offset Vo ltage Ta=2 5℃ （ Note 5） Input Bias Current Ta=2 5℃ , I I N ( + ) or I I N （ - ） , V C M =0V （ Note 6） Min. Input Offset Current Ta=2 5℃ ， I I N ( + ) - I I N （ - ）， V C M =0V Input Common-Mode Ta=2 5℃ ， V + =30V（ Note 7） Vo ltage Range Over Full Temperature V + =30V Supply Current Range, R L =∞ on all Op V + =5V Amps + Larg e Signal Vo ltage V =15V， Ta=2 5℃ ， R L ≥2 k Ω Gain （ For Vo =1~11V） Co mmon-M ode DC， Ta=2 5℃ ， V C M =0~V + -1.5V Rejection Ratio Power Supply DC， Ta=2 5℃ ， V + =5~30V Rejection Ratio Amplifier-to-Amplifier Ta=2 5℃ ， f=1~20kHz Coupling （ Input Referred）（ Note 8） V I N ( + ) =1V,V I N ( - ) =0V,V + =15V,Vo=2V, Source Ta=2 5℃ V I N ( - ) =1V,V I N ( + ) =0V,V + =15V,Vo=2V, Output Current Ta=2 5℃ Sink V I N ( - ) =1V,V I N ( + ) =0V,V + =15V, Vo=200mV,Ta=25℃ Output Vo ltage Swing Max. Unit 2 5 mV 45 150 nA 3 30 nA V + -1.5 V 0 1 2 0.5 1.2 100 V/mV 70 90 dB 75 100 dB -120 dB 20 40 mA 10 20 mA 12 50 µA 40 （ Note 5） 60 mA 7 mV µV/℃ 7 Rs=0Ω IIN(+) - IIN（ -） 100 Rs=0Ω 10 I I N ( + ) or I I N （ - ） 40 V + =30V（ Note 7） mA 50 Short Circuit to Ground V + =15V， Ta=2 5℃ （ Note 2 ） Input Offset Vo ltage Input Offset Vo ltage Drift Input Offset Current Input Offset Current Drift Input Bias Current Input Common-Mode Vo ltage Range Larg e Signal Vo ltage Gain Typ. 0 nA pA/℃ 300 V+2 nA V V + =15V，（ Vo=1~11V）， R L ≥2 k Ω 25 V/mV R L =2kΩ 26 V R L =10kΩ 27 VOH V + =30V VOL V + =5V， R L =10kΩ 28 5 V 20 mV + Output Current Source Sink V I N ( + ) =1V ， V I N ( - ) =0V ， V =15V ， Vo=2V V I N ( - ) =1V ， V I N ( + ) =0V ， V + =15V ， Vo=2V 10 20 mA 5 8 mA 3/8 LM2904N/D Note 1 The dissipation is the total of both amplifiers—use external resistors, where possible, to allow the amplifier to saturate or to reduce the power which is dissipated in the integrated circuit. Note 2: Short circuits from the output to V + can cause excessive heating and eventual destruction. W h e n c o n s i d e r i n g s h o r t c i r c u i t s t o g r o u n d , t he m a x i m u m o u t p u t c u r r e n t i s a p p r o x i m a t e l y 4 0 m A independent of the magnitude of V + . At values of supply voltage in excess of +15V, continuous short-circuits can exceed the power dissipation ratings and cause eventual destruction. Destructive dissipation can result from simultaneous shorts on all amplifiers. Note 3: This input current will only exist when the voltage at any of the input leads is driven negative. It is due to the collector-base junction of the input PNP transistors becoming forward biased and t h e r e b y a c t i n g a s i n p u t d i o d e c l a m p s . I n a d d i t i o n t o t hi s d i o d e a c t i o n , t h e r e i s a l s o l a t e r a l N P N p a r a s i t i c transistor action on the IC chip. This transistor action can cause the output voltages of the op amps to go to the V + voltage level (or to ground for a large overdrive) for the time duration that an input is driven negative. This is not destructive and normal output states will re-establish when the input voltage, which was negative, again returns to a value greater than -0.3V (at 25°C). N o t e 4 : W i t h t h e D 3 5 8 , a l l t e m p e r a t u r e s p e c i f i c a t i o n s a r e l i m i t e d t o - 2 5 ℃ ≤ Ta ≤ 8 5 ℃ . Note 5: Vo=1.4V, Rs = 0Ω with V + from 5V to 30V; and over the full input common-mode range (0V to V + -1.5V) at 25°C Note 6: The direction of the input current is out of the IC due to the PNP input stage. This current is essentially constant, independent of the state of the output so no loading change exists on the input lines. Note 7: The input common-mode voltage of either input signal voltage should not be allowed to go negative by more than 0.3V (at 25°C). The upper end of them common-mode voltage range is V + -1.5V (at 25°C), but either or both inputs can go to +32V without damage, independent of the magnitude of V+. N o t e 8 : D u e t o p r o x i m i t y o f e x t e r n a l c o m p o n e n t s , i n s ur e t h a t c o u p l i n g i s n o t o r i g i n a t i n g v i a s t r a y capacitance between these external parts. This typically can be detected as this type of capacitance increases at higher frequencies. 4/8 LM2904N/D TYPICAL SINGLE-SUPPLY APPLICATION CIRCUIT Non-Inverting DC Gain (0V output) +5V +V IN * + 1/2 LM2904 D358 - Vo(V) +Vo R2 1M R1 10K Gain=1+R2/R1 =101 （as shown ） 0 * R not needed due to temperature independent I DC Summing Amplifier VIN(mV) Power Amplifier （ VIN'S ≥0V, and Vo≥0V) R 100K +V1 +V2 + R 1/2 LM2904 D358 100K - R 100K R 100K +V3 +V4 R1 +Vo 100K R3 R +V IN 91K 100K R 100K 910K R2 + V + LM2904 1/2 D358 - +Vo RL I N =0 V, Av =1 0 Vo =0 V fo r V Where Vo=V1+V2+V3+V4 (V1+V2)≥(V3+V4) to Keep Vo>0V "BI-QUAD" RC Active Bandpass Filter R1 Fixed Current Sources V+ 100K C1 + R2 VIN 100K R3 100K 1/2 LM2904 D358 330pF R4 C2 330pF 470K LM2904 1/2 D358 10M - - LM2904 1/2 D358 + R6 - LM2904 1/2 D358 fo=1kHz Q=50 Av=100(40dB) R5 + + Vo 470K R7 R8 100K C3 10uF + 2V R1 R2 - 2K + R3 2V - 2K + 100K V R4 3K I1 I2 1mA I2=(R1/R2)*I1 5/8 LM2904N/D APPLICATION HINTS The LM2904 is op amps which operate with only a single power supply voltage, have true-differential inputs, and remain in the linear mode with an input common-mode voltage of 0V. These amplifiers operate over a wide range of power supply voltage with little change in performance characteristics. At 25°C amplifier operation is possible down to a minimum supply voltage of 2.3 V. Precautions should be taken to insure that the power supply for the integrated circuit never becomes reversed in polarity or that th e unit is not inadvertently installed backwards in a test socket as an unlimited current surge through the resulting forward diode within the IC could cause fusing of the internal conductors and result in a destroyed unit. Large differential input voltages can be easily accommodated and, as input differential voltage protection diodes are not needed, no large input currents result from large differential input voltages. The differential input voltage may be larger than V + without damaging the device. Protection should be provided to prevent the input voltages from going negative more than -0.3V (at 25°C). An input clamp diode with a resistor to the IC input terminal can be used. To reduce the power supply current drain, the amplifiers have a class A output stage for small signal levels which converts to class B in a large signal mode. This allows the amplifiers to both source and sink large output currents. Therefore both NPN and PNP external current boost transistors can be used to extend the power capability of the basic amplifiers. The output voltage needs to raise approximately 1 diode drop above ground to bias the on-chip vertical PNP transistor for output current sinking applications. For ac applications, where the load is capacitively coupled to the output of the amplifier, a resistor should be used, from the output of the amplifier to ground to increase the class A bias current and prevent crossover distortion. Wh ere the load is directly coupled, as in dc applications, there is no crossover distortion. Capacitive loads which are applied directly to the output of the amplifier reduce the loop stability margin. Values of 50pF can be accomodated using the worst-case non-inverting unity gain connection. Large closed loop gains or resistive isolation should be used if larger load capacitance must be driven by the amplifier. Output short circuits either to ground or to the positive power suppl y should be of short time duration. Units can be destroyed, not as a result of the short circuit current causing metal fusing, but rather due to the large increase in IC chip dissipation which will cause eventual failure due to excessive function temperatures. Putting direct short-circuits on more than one amplifier at a time will increase the total IC power dissipation to destructive levels, if not properly protected with external dissipation limiting resistors in series with the output leads of the amplifiers. The larg er value of output source current which is available at 25°C provides a larger output curre nt capability at elevated temperatures (see typical performance characteristics) than a standard IC op amp. 6/8 LM2904N/D TYPICAL PERFORMANCE CHARACTERISTICS 7/8 LM2904N/D 8/8