LS204 HIGH PERFORMANCE DUAL OPERATIONAL AMPLIFIERS .. .. . LOW POWER CONSUMPTION SHORT CIRCUIT PROTECTION LOW DISTORTION, LOW NOISE HIGH GAIN-BANDWIDTH PRODUCT HIGH CHANNEL SEPARATION N DIP8 (Plastic Package) DESCRIPTION The LS204 is a high performance dual operational amplifier with frequency and phase compensation built intothe chip. The internal phasecompensation allows stable operation as voltage follower in spite of its high Gain-Bandwidth Product. The circuit presents very stable electrical characteristics over the entire supply voltage range, and is particularlyintended for professional and telecom applications (active filter, etc). D SO8 (Plastic Micropackage) ORDER CODES Part Number LS204C Temperature Range N D 0, +70oC • • o • • -40, +105 C LS204I Package PIN CONNECTIONS (top view) 8 VCC + 7 Output - 6 Non-inve rting Input 2 + 5 Inve rting Input 2 Output 1 1 Inve rting Input 1 2 - Non-inve rting Input 1 3 + VCC - 4 April 1998 1/10 LS204 SCHEMATIC DIAGRAM (1/2 LS204) ABSOLUTE MAXIMUM RATINGS Symbol Value Unit Supply Voltage ±18 V Vi Input Voltage ±VCC Vid Differential Input Voltage VCC ± (VCC - 1) Operating Temperature Range Ptot Power Dissipation at Tamb = 70oC 500 Junction Temperature 150 o -65 to +150 o Tstg Storage Temperature Range LS204C LS204I 0 to +70 -40 to +105 o Toper Tj 2/10 Parameter C mW C C LS204 ELECTRICAL CHARACTERISTICS (VCC = ±15V, Tamb = 25oC, unless otherwise specified) Symbol Parameter Test Conditions LS204I Min. Typ. LS204C Max. Min. Typ. Max. Unit ICC Supply Current 0.7 1.2 0.8 1.5 mA Iib Input Bias Current 50 150 100 300 nA Ri Input Resistance Vio Input Offset Voltage Tmin. < Top < Tmax. 300 f = 1kHz Rs ≤ 10kΩ 0.5 Rs ≤ 10kΩ Tmin. < Top < Tmax. DVio Iio Input Offset Voltage Drift Ios Output Short Circuit Current Avd Large Signal Voltage Gain GBP en 2.5 0.5 2 5 12 40 Tmin. < Top < Tmax. nA °C 23 23 mA 90 100 95 86 100 95 Gain-Bandwidth Product f = 100kHz 1.8 3 1.5 2.5 Equivalent Input Noise Voltage f = 1kHz Rs = 50Ω Rs = 1kΩ Rs = 10kΩ dB 8 10 18 15 10 12 20 0.03 0.1 0.03 Output Voltage Swing RL = 2kΩ VCC = ±15V VCC = ±4V Vopp Large Signal Voltage Swing RL = 10kΩ f = 10kHz Slew Rate Unity Gain, RL = 2kΩ 0.8 Common Mode Rejection Ratio Vic = 10V Tmin. < Top < Tmax. 90 86 Vic = 1V f = 100Hz Tmin. < Top < Tmax. 90 86 f = 1kHz 100 Channel Separation nA nA 0.1 ±Vopp VO1 /VO2 50 100 0.08 Tmin. < Top < Tmax. RL = 2kΩ VCC = ±15V VCC = ±4V Supply Voltage Rejection Ratio µV/ C 2 20 AV = 20dB R L = 2kΩ VO = 2VPP f = 1kHz SVR mV o Rs ≤ 10kΩ Tmin. < Top < Tmax. Total Harmonic Distortion SR 3.5 5 THD CMR nA MΩ mV Tmin. < Top < Tmax. Input Offset Current Drift 1 3.5 Input Offset Current DIio 700 1 ±13 ±3 ±13 ±3 MHz nV √ Hz 0.1 % V 28 28 VPP 1.5 1 V/µs dB dB 120 120 dB 3/10 LS204 4/10 LS204 5/10 LS204 APPLICATION INFORMATION : Active low-pass filter BUTTERWORTH The Butterworth is a ”maximally flat” amplitude response filter (figure 10) Butterworth filters are used for filtering signals in data acquisition systems to prevent aliasing errors in samples-data applications and for general purpose low-pass filtering. The cut-off frequency Fc, is the frequency at which the amplitude response is down 3dB. The attenuation rate beyond the cutoff frequency is n6 dB per octave of frequency where n is the order (number of poles) of the filter. Other characteristics : Flattest possible amplitude response Excellent gain accuracy at low frequency end of passband .. BESSEL The Bessel is a type of ”linear phase” filter. Because of their linear phase characteristics, these filters approximate a constant time delay over a limited frequency range. Bessel filters pass transient waveforms with a minimum of distortion. They are also used to provide time delays for low pass filtering of modulated waveforms and as a ”running average” type filter. −nΠ The maximum phase shift is radians where n 2 is the order (number of poles) of the filter. The cut-off frequency fc, is defined as the frequency at which the phase shift is one half of this value. For accurate delay, the cut-off frequency should be twice the maximum signal frequency. The following table can be used to obtain the -3dB frequency of the filter. -3dB Frequency . .. 2 Pole 4 Pole 6 Pole 8 Pole 0.77fc 0.67fc 0.57fc 0.50fc Other characteristics : Selectivity not as great as Chebyschev or Butterworth Very little overshoot response to step inputs Fast rise time CHEBYSCHEV Chebyschev filters have greater selectivity than either Bessel ro Butterworth at the expense of ripple in the passband (figure 11). Chebyschev filters are normally designed with peak-to-peak ripple values from 0.2dB to 2dB. Increased ripple in the passband allows increased attenuation above the cut-off frequency. The cut-off frequency is defined as the frequency at which the amplitude response passes through the specificed maximum ripple band and enters the stop band. Other characteristics : Greater selectivity Very non-linear phase response High overshoot response to step inputs .. . The table below shows the typical overshoot and settling time response of the low pass filters to a step input. Number of Poles Peak Overshoot Settling Time (% of final value) % Overshoot ±1% ±0.1% ±0.01% Butterworth 2 4 6 8 4 11 14 16 1.1Fcsec. 1.7/fc 2.4/fc 3.1/fc 1.7Fcsec. 2.8/fc 3.9/fc 5.1/fc 1.9Fcsec. 3.8/fc 5.0/fc 7.1/fc Bessel 2 4 6 8 0.4 0.8 0.6 0.1 0.8/fc 1.0/fc 1.3/fc 1.6/fc 1.4/fc 1.8/fc 2.1/fc 2.3/fc 1.7/fc 2.4/fc 2.7/fc 3.2/fc Chebyschev (ripple ±0.25dB) 2 4 6 8 11 18 21 23 1.1/fc 3.0/fc 5.9/fc 8.4/fc 1.6/fc 5.4/fc 10.4/fc 16.4/fc - Chebyschev (ripple ±1dB) 2 4 6 8 21 28 32 34 1.6/fc 4.8/fc 8.2/fc 11.6/fc 2.7/fc 8.4/fc 16.3/fc 24.8/fc - Design of 2nd order active low pass filter (Sallen and Key configuration unity gain-op-amp) 6/10 LS204 7/10 LS204 8/10 LS204 PACKAGE MECHANICAL DATA 8 PINS - PLASTIC DIP Dim. Millimeters Min. A a1 Typ. Inches Max. Min. 3.32 Typ. Max. 0.131 0.51 0.020 B 1.15 1.65 0.045 0.065 b 0.356 0.55 0.014 0.022 b1 0.204 0.304 0.008 D E 0.012 10.92 7.95 9.75 0.430 0.313 0.384 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 F 6.6 0260 i 5.08 0.200 L Z 3.18 3.81 1.52 0.125 0.150 0.060 9/10 LS204 PACKAGE MECHANICAL DATA 8 PINS - PLASTIC MICROPACKAGE (SO) Dim. A a1 a2 a3 b b1 C c1 D E e e3 F L M S Min. Millimeters Typ. 0.1 0.65 0.35 0.19 0.25 Max. 1.75 0.25 1.65 0.85 0.48 0.25 0.5 Min. Inches Typ. 0.026 0.014 0.007 0.010 Max. 0.069 0.010 0.065 0.033 0.019 0.010 0.020 0.189 0.228 0.197 0.244 0.004 45o (typ.) 4.8 5.8 5.0 6.2 1.27 3.81 3.8 0.4 0.050 0.150 4.0 1.27 0.6 0.150 0.016 0.157 0.050 0.024 o 8 (max.) Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without noti ce. This publication supersedes and replaces all information previously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics. 1998 SGS-THOMSON Microelectronics – Printed in Italy – All Rights Reserved SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - France - Germany - Italy - Japan - Korea - Malaysia - Malta - Morocco The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A. 10/10