EL8178 ® Data Sheet PRELIMINARY October 5, 2005 Micropower Single Supply Rail-to-Rail Input-Output Precision Op Amp The EL8178 is a micropower precision operational amplifier optimized for single supply operation at 5V and can operate down to 2.4V. The EL8178 draws minimal supply current while meeting excellent DC-accuracy noise and output drive specifications. Competing devices seriously degrade these parameters to achieve micropower supply current. Offset current, voltage and current noise, slew rate, and gain-bandwidth product are all two to ten times better than on previous micropower op amps. The EL8178 can be operated from one lithium cell or two Ni-Cd batteries. The input range includes both positive and negative rail. The output swings to both rails. Ordering Information TAPE & REEL EL8178AIW-T7 BBHA 7” (3K pcs) EL8178AIW-T7A BBHA 7”| 6 Ld SOT-23 MDP0038 (250 pcs) EL8178AIWZ-T7 (Note) BBPA 7” (3K pcs) PACKAGE PKG. DWG. # 6 Ld SOT-23 MDP0038 6 Ld SOT-23 MDP0038 (Pb-free) EL8178AIWZ-T7A BBPA (Note) 7” 6 Ld SOT-23 MDP0038 (250 pcs) (Pb-free) EL8178BIW-T7 BBHA 7” (3K pcs) EL8178BIW-T7A BBHA 7” 6 Ld SOT-23 MDP0038 (250 pcs) EL8178BIWZ-T7 (Note) BBPA EL8178BIWZ-T7A BBPA (Note) Features • 50µA supply current • 100µV max offset voltage • 1pA input bias current • 250kHz gain-bandwidth product • 0.13V/µs slew rate • Single supply operation down to 2.4V • Rail-to-rail input and output • Output sources and sinks 26mA load current • Pb-Free plus anneal available (RoHS compliant) Applications • Battery- or solar-powered systems • 4mA to 20mA current loops PART MARKING PART NUMBER FN7504.2 7” (3K pcs) • Handheld consumer products • Medical devices • Thermocouple amplifiers • Photodiode pre amps • pH probe amplifiers Pinouts EL8178 (6 LD SOT-23) TOP VIEW 6 Ld SOT-23 MDP0038 6 Ld SOT-23 MDP0038 (Pb-free) OUT 1 VS- 2 8178ISZ - 8 Ld SO (Pb-free) MDP0027 EL8178ISZ-T7 (Note) 8178ISZ 7” 8 Ld SO (Pb-free) MDP0027 EL8178ISZ-T13 (Note) 8178ISZ 8 Ld SO (Pb-free) MDP0027 13” 5 ENABLE 4 IN- EL8178 (8 LD SO) TOP VIEW NC 1 NOTE: Intersil Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 1 + - IN+ 3 7” 6 Ld SOT-23 MDP0038 (250 pcs) (Pb-free) EL8178ISZ (Note) 6 VS+ IN- 2 IN+ 3 VS- 4 8 ENABLE + 7 VS+ 6 VOUT 5 NC CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright © Intersil Americas Inc. 2004, 2005. All Rights Reserved. All other trademarks mentioned are the property of their respective owners. EL8178 Absolute Maximum Ratings (TA = 25°C) Output Short-Circuit Duration . . . . . . . . . . . . . . . . . . . . . . .Indefinite Ambient Operating Temperature Range . . . . . . . . . .-40°C to +85°C Storage Temperature Range . . . . . . . . . . . . . . . . . .-65°C to +150°C Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5V Current into IN+, IN-, or ENABLE. . . . . . . . . . . . . . . . . . . . . . . . 5mA Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to VS + 0.5V CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA Electrical Specifications PARAMETER VOS VS = 5V, 0V, VCM = 0.1V, VO = 1.4V, TA = 25°C unless otherwise specified. DESCRIPTION Input Offset Voltage CONDITIONS MIN TYP MAX UNIT Grade A 50 100 µV Grade B 110 400 µV ∆V OS -----------------∆Time Long Term Input Offset Voltage Stability ∆V OS ---------------∆T Input Offset Drift vs Temperature IB Input Bias Current eN Input Noise Voltage Density fO = 1kHz CMIR Input Voltage Range Guaranteed by CMRR test CMRR Input Voltage Range CMRR Common-Mode Rejection Ratio VCM = 0V to 5V 80 100 dB PSRR Power Supply Rejection Ratio VS = 3.3V to 5V 80 100 dB AVOL Large Signal Voltage Gain VO = 0.5V to 4.5V, RL = 100kΩ 100 400 V/mV VO = 0.5V to 4.5V, RL = 1kΩ 15 V/mV Output low, RL = 100kΩ 3 6 mV 130 200 mV VOUT Maximum Output Voltage Swing TBD µV/Mo EL8178IW 1.9 µV/°C EL8178IS 1.1 µV/°C 1 Output high, RL = 1kΩ pA 35 nV/√Hz 0 5 V 0 5 V Output low, RL = 1kΩ Output high, RL = 100kΩ 50 4.994 4.997 V 4.8 4.88 V 0.09 0.13 SR Slew Rate GBW Gain Bandwidth Product IS,ON Supply Current, Enabled IS,OFF Supply Current, Disabled IO+ Short Circuit Output Current RL = 10Ω 18 31 mA IO- Short Circuit Output Current RL = 10Ω 17 26 mA VS Minimum Supply Voltage VINH Enable Pin High Level VINL Enable Pin Low Level IENH Enable Pin Input Current VEN = 5V 0.25 0.7 2 µA IENL Enable Pin Input Current VEN = 0V -0.5 0 +0.5 µA 2 fO = 100kHz 0.17 400 40 V/µs kHz 50 75 µA 3 10 µA 2.2 2.4 V 2 V 0.8 V FN7504.2 October 5, 2005 EL8178 Typical Performance Curves 1 80 Gain = 1K Gain = 500 60 0 50 VS = ±1.25 GAIN (dB) MAGNITUDE (dB) 70 -1 VS = ±2.5V Gain = 200 40 Gain = 100 Gain = 10 30 Gain = 5 20 10 -2 Gain = 2 0 VS = ±1.0V -3 1K 10K -10 100K -20 1M Gain = 1V/V 1 10 100 FREQUENCY (Hz) 200 INPUT OFFSET VOLTAGE (µV) SUPPLY CURRENT (µA) 50 40 30 20 10 2.5 3 4 3.5 4.5 5 100 0 -100 -200 -0.5 5.5 0.5 150 50 -50 -150 2.5 3.5 4.5 5.5 COMMON-MODE INPUT VOLTAGE (V) FIGURE 5. INPUT OFFSET VOLTAGE vs COMMON-MODE INPUT VOLTAGE 3 2.5 3.5 4.5 5.5 FIGURE 4. INPUT OFFSET VOLTAGE vs OUTPUT VOLTAGE INPUT BIAS, OFFSET CURRENT (fA) INPUT OFFSET VOLTAGE (µV) 250 1.5 1.5 OUTPUT VOLTAGE (V) FIGURE 3. SUPPLY CURRENT vs SUPPLY VOLTAGE 0.5 10M AV = -1 VCM = VDD/2 SUPPLY VOLTAGE (V) -250 -0.5 100K 1M FIGURE 2. FREQUENCY RESPONSE vs CLOSED LOOP GAIN 60 2 10K FREQUENCY (Hz) FIGURE 1. UNITY GAIN FREQUENCY RESPONSE vs SUPPLY VOLTAGE 0 1K 20 IOS 10 IB0 -10 -20 -0.5 IB+ 0.5 1.5 2.5 3.5 4.5 5.5 COMMON-MODE INPUT VOLTAGE (V) FIGURE 6. INPUT BIAS, OFFSET CURRENT vs COMMONMODE INPUT VOLTAGE FN7504.2 October 5, 2005 EL8178 (Continued) 200 80 150 PHASE GAIN (dB) 60 50 40 0 20 GAIN GAIN (dB) 100 -50 0 -100 -20 10 100 1K 100K 10K -150 1M 110 100 90 80 70 60 50 40 30 20 10 0 -10 -20 -30 -40 100 80 60 PHASE 40 20 GAIN 1 10 100 CMRR (dB) 100 80 60 40 20 1K 10K 100K 1M 120 110 100 90 80 70 60 50 40 30 20 10 0 -10 -20 100K -40 10M 1M PSRR+ PSRR- 1 10 100 1K 10K 100K 1M FREQUENCY (Hz) FREQUENCY (Hz) FIGURE 9. CMRR vs FREQUENCY FIGURE 10. PSRR vs FREQUENCY 150 INPUT OFFSET VOLTAGE (µV) 1000 VOLTAGE NOISE (nV/√Hz) 10K FIGURE 8. OPEN LOOP GAIN AND PHASE vs FREQUENCY @ 100kΩ POWER SUPPLY REJECTION RATIO (dB) 120 100 1K FREQUENCY (Hz) FIGURE 7. AVOL vs FREQUENCY @ 1kΩ LOAD 10 0 -20 FREQUENCY (Hz) 0 1 PHASE (°) 100 PHASE (°) Typical Performance Curves 100 10 1 1 10 100 1K 10K FREQUENCY (Hz) FIGURE 11. VOLTAGE NOISE 4 100K 10 SAMPLES 100 50 0 -50 -100 -150 0 10 20 30 40 50 60 70 80 90 100 TEMPERATURE (°C) FIGURE 12. VOS vs TEMPERATURE FN7504.2 October 5, 2005 EL8178 (Continued) 400 800 300 600 200 400 100 200 VOS (µV) VOS (µV) Typical Performance Curves 0 -100 35 6-PIN SOT23 SAMPLES TYPICAL = 1.9µV/C 0 -200 -200 -400 35 SOIC SAMPLES TYPICAL = 1.1µV/C -300 -400 -60 -40 -20 0 20 40 60 80 -600 -800 -60 100 120 -40 -20 TEMPERATURE (°C) FIGURE 13. EL8178 SOIC VOS vs TEMPERATURE (VS = 5V) 0.7 SO T2 θJ 3-6 A =2 30 °C /W 0.4 0.2 0 0 25 50 75 85 100 125 150 AMBIENT TEMPERATURE (°C) FIGURE 15. PACKAGE POWER DISSIPATION vs AMBIENT TEMPERATURE 5 80 100 120 JEDEC JESD51-3 LOW EFFECTIVE THERMAL CONDUCTIVITY TEST BOARD 0.6 625mW 0.5 8 /W SO 0°C 6 =1 435mW 60 A A 8 /W S O 0° C 1 =1 0.6 40 θJ POWER DISSIPATION (W) 909mW 0.8 20 FIGURE 14. EL8178 SOT VOS vs TEMPERATURE (VS = 5V) JEDEC JESD51-7 HIGH EFFECTIVE THERMAL CONDUCTIVITY TEST BOARD θJ POWER DISSIPATION (W) 1 0 TEMPERATURE (°C) 0.4 391mW θ 0.3 SO JA = 0.2 25 T2 3- 6 6° C/ W 0.1 0 0 25 50 75 85 100 125 150 AMBIENT TEMPERATURE (°C) FIGURE 16. PACKAGE POWER DISSIPATION vs AMBIENT TEMPERATURE FN7504.2 October 5, 2005 EL8178 Applications Information Typical Applications Introduction The EL8178 is a rail-to-rail input and output micro-power precision single supply operational amplifier with an enable feature. The device achieves rail-to-rail input and output operation and eliminates the concerns introduced by a conventional rail-to-rail I/O operational Amplifier. V+ + EL8178 V- GENERAL PURPOSE COMBINATION pH PROBE + COAX 3V FIGURE 17. PH PROBE AMPLIFIER Rail-to-Rail Input The PFET input stage of the EL8178 has an input commonmode voltage range that goes from negative supply to positive supply without introducing offset errors or degrading performance associated with a conventional rail-to-rail input operational amplifier. Many rail-to-rail input stages use two differential input pairs, a long-tail PNP (or PFET) and an NPN (or NFET). Severe penalties have to be paid for this topology. As the input signal moves from one supply rail to another, the operational amplifier switches from one input pair to the other causing drastic changes in input offset voltage and an undesired change in magnitude and polarity of input offset current. The EL8178 achieves input rail-to-rail performance without sacrificing important precision specifications and without degrading distortion performance. The EL8178's input offset voltage exhibits a smooth behavior throughout the entire common-mode input range. Rail-to-Rail Output A pair of complementary MOSFET devices achieves rail-torail output swing. The NMOS sinks current to swing the output in the negative direction. The PMOS sources current to swing the output in the positive direction. The EL8178 with a 100kΩ load will swing to within 3mV of the supply rails. Enable/Disable Feature The EL8178 offers an EN pin. The active low enable pin disables the device when pulled up to at least 2.2V. Upon disable the part consumes typically 3µA, while the output is in a high impedance state. The EN also has an internal pull down. If left open, the EN pin will pull to negative rail and the device will be enabled by default. The high impedance at output during disable allows multiple EL8178s to be connected together as a MUX. The outputs are tied together in parallel and a channel can be selected by the EN pin. 6 A general-purpose combination pH probe has extremely high output impedance typically in the range of 10GΩ to 12GΩ. Low loss and expensive Teflon cables are often used to connect the PH probe to the meter electronics. The above circuit provides a low-cost alternative solution using the EL8178 and a low-cost coax cable. The EL8178 PMOS high impedance input senses the pH probe output signal and buffers it to drive the coax cable. Its rail-to-rail input nature also eliminates the need for a bias resistor network required by other amplifiers in the same application. R4 100kΩ R3 10kΩ R2 K TYPE THERMOCOUPLE 10kΩ V+ + EL8178 V- 410µV/°C + 5V R1 100kΩ FIGURE 18. THERMOCOUPLE AMPLIFIER Thermocouples are the most popular temperature-sensing device because of their low cost, interchangeability, and ability to measure a wide range of temperatures. The EL8178 is used to convert the differential thermocouple voltage into single-ended signal with 10X gain. The EL8178's rail-to-rail input characteristic allows the thermocouple to be biased at ground and the converter to run from a single 5V supply. FN7504.2 October 5, 2005 EL8178 SO Package Outline Drawing 7 FN7504.2 October 5, 2005 EL8178 SOT-23 Package Outline Drawing NOTE: The package drawing shown here may not be the latest version. To check the latest revision, please refer to the Intersil website at http://www.intersil.com/design/packages/index.asp All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems. Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements 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 Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 8 FN7504.2 October 5, 2005