® OPA2541 Dual High Power OPERATIONAL AMPLIFIER FEATURES DESCRIPTION ● OUTPUT CURRENTS TO 5A ● POWER SUPPLIES TO ±40V ● FET INPUT The OPA2541 is a dual power operational amplifier capable of operation from power supplies up to ±40V and output currents of 5A continuous. With two monolithic power amplifiers in a single package it provides unequaled functional density. ● ELECTRICALLY ISOLATED CASE The industry-standard 8-pin TO-3 package is isolated from all internal circuitry allowing it to be mounted directly to a heat sink without insulators which degrade thermal performance. Internal circuitry limits output current to approximately 6A. APPLICATIONS ● ● ● ● ● MOTOR DRIVER SERVO AMPLIFIER SYNCRO/RESOLVER EXCITATION VOICE COIL DRIVER BRIDGE AMPLIFIER The OPA2541 is available in both industrial and military temperature range versions. ● PROGRAMMABLE POWER SUPPLY ● AUDIO AMPLIFIER +VS (2) –In (4, 8) +In (3, 7) Out (5, 1) –VS (6) International Airport Industrial Park • Mailing Address: PO Box 11400 Tel: (520) 746-1111 • Twx: 910-952-1111 • Cable: BBRCORP • © 1987 Burr-Brown Corporation • Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd. • Tucson, AZ 85706 Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132 PDS-768B Printed in U.S.A. October, 1993 SPECIFICATIONS ELECTRICAL At TC = +25°C and VS = ±35VDC, unless otherwise noted. OPA2541AM PARAMETER CONDITIONS MIN OPA2541BM, SM TYP MAX ±2 ±20 ±2.5 ±20 Specified Temperature Range Specified Temperature Range MIN TYP MAX UNITS ±10 ±40 ±10 ±60 ±0.25 ±15 * * ±1 ±30 * * mV µV/°C µV/V µV/W 15 Note 1 50 * * * pA ±5 Note 1 ±30 * * * pA INPUT OFFSET VOLTAGE VOS vs Temperature vs Supply Voltage vs Power Specified Temperature Range VS = ±10V to ±VMAX INPUT BIAS CURRENT IB INPUT OFFSET CURRENT IOS INPUT CHARACTERISTICS Common-Mode Voltage Range Common-Mode Rejection Input Capacitance Input Impedance, DC Specified Temperature Range VCM = (|±VS| –6V) ±(|VS| –6) 95 ±(|VS| –3) 106 5 1 * * * * * * V dB pF 1012Ω RL = 6Ω 90 96 1.6 * * * dB MHz * * * * * 3 * * * * 3.5 V V V A A A * * * V/µs kHz µs GAIN CHARACTERISTICS Open Loop Gain at 10Hz Gain-Bandwidth Product OUTPUT Voltage Swing Current, Continuous IO = 5A IO = 2A IO = 0.5A +25°C +85°C +125°C (SM grade only) ±(|VS| –5.5) ±(|VS| –4.5) ±(|VS| –4.5) ±(|VS| –3.6) ±(|VS| –4) ±(|VS| –3.2) 5 7.0 4 5.0 AC PERFORMANCE Slew Rate Power Bandwidth Settling Time to 0.1% Capacitive Load Phase Margin Channel Separation 6 45 RL = 8Ω, VO = 20Vrms 2V Step Specified Temperature Range, G = 1 Specified Temperature Range, G >10 Specified Temperature Range, RL = 8Ω 1kHz, RL = 6Ω 8 55 2 * * 3.3 SOA * * 40 80 * * nF Degrees dB POWER SUPPLY Power Supply Voltage, ±VS Current, Quiescent ±10 Specified Temperature Range Total—Both Amplifiers ±30 40 ±35 50 0.8 0.9 1.25 1.4 30 1.0 1.2 1.5 1.9 * ±35 * ±40 * V mA * * * * * * * * * °C/W °C/W °C/W °C/W °C/W * +125 °C °C THERMAL RESISTANCE θJC, (Junction-to-Case) θJC θJC θJC θJA, (Junction-to-Ambient) Both Amplifiers(2), AC Output f > 60Hz Both Amplifiers(2), DC Output One Amplifier, AC Output f > 60Hz One Amplifier, DC Output No Heat Sink TEMPERATURE RANGE Case AM, BM SM –25 +85 * –55 *Specification same as OPA2541AM. NOTES: (1) Input bias and offset current approximately doubles for every 10°C increase in temperature. (2) Assumes equal dissipation in both amplifiers. The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems. ® OPA2541 2 ABSOLUTE MAXIMUM RATINGS CONNECTION DIAGRAM Supply Voltage, +VS to –VS .................................................................. 80V Output Current ............................................................................. see SOA Power Dissipation, Internal(1) ............................................................ 125W Input Voltage: Differential ..................................................................... ±VS Common-mode ............................................................. ±VS Temperature: Pin Solder, 10s ........................................................ +300°C Junction(1) ............................................................... +150°C Temperature Range: Storage .................................................... –65°C to +150°C Operating (Case) ..................................... –55°C to +125°C Top View TO-3 +VS +InA 2 3 1 OutB –InA 4 OutA 5 A B 8 –VS NOTE: (1) Long term operation at the maximum junction temperature will result in reduced product life. Derate internal power dissipation to achieve high MTTF. 6 –InB 7 +InB PACKAGE INFORMATION MODEL PACKAGE PACKAGE DRAWING NUMBER(1) TO-3 TO-3 TO-3 030 030 030 OPA2541AM OPA2541BM OPA2541SM NOTE: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix D of Burr-Brown IC Data Book. ORDERING INFORMATION MODEL PACKAGE TEMPERATURE RANGE OPA2541AM OPA2541BM OPA2541SM TO-3 TO-3 TO-3 –25°C to +85°C –25°C to +85°C –55°C to +125°C TYPICAL PERFORMANCE CURVES TA = +25°C and VS = ±35VDC, unless otherwise noted. INPUT BIAS CURRENT vs TEMPERATURE OPEN-LOOP GAIN AND PHASE vs FREQUENCY Voltage Gain (dB) 10 1 0.1 0.01 0.001 –25 0 25 50 75 100 125 110 100 90 80 70 60 50 40 30 20 10 0 –10 Phase Gain ZL = 3.3nF ZL = 2kΩ ZL = 3.3nF 1 Junction Temperature (°C) ZL = 2kΩ 0 –45 –90 –135 –180 Phase (Degrees) Input Bias Current (nA) 100 10 100 1k 10k 100k 1M 10M Frequency (Hz) ® 3 OPA2541 TYPICAL PERFORMANCE CURVES (CONT) TA = +25°C and VS = ±35VDC, unless otherwise noted. NORMALIZED QUIESCENT CURRENT vs TOTAL POWER SUPPLY VOLTAGE OUTPUT VOLTAGE SWING vs OUTPUT CURRENT 1.3 6 1.2 5 (+VS) – VO |±VS| – |VOUT| (V) Normalized IQ 1.1 TC = –25°C 1.0 TC = +25°C 0.9 0.8 TC = +125°C 4 |–VS| – |VO| 3 2 1 0.7 0.6 0 20 40 30 50 60 70 80 0 90 1 2 3 6 8 7 9 10 10 1.0 THD + Noise (%) Voltage Noise Density (nV/√Hz) 5 TOTAL HARMONIC DISTORTION vs FREQUENCY VOLTAGE NOISE DENSITY vs FREQUENCY 1k 100 PO = 100mW 0.1 PO = 5W PO = 50W 0.01 0.001 10 1 10 100 1k 10k 10 100k 1k 100 10k 100k Frequency (Hz) Frequency (Hz) COMMON-MODE REJECTION vs FREQUENCY OUTPUT CURRENT vs TEMPERATURE 120 12 110 10 Output Current (A) 100 CMRR (dB) 4 IOUT (A) +VS + |–VS| (V) 90 80 70 8 IOUT– 6 IOUT+ 4 2 60 50 0 10 100 1k 10k 100k 1M –50 Frequency (Hz) 0 25 50 Case Temperature (°C) ® OPA2541 –25 4 75 100 125 TYPICAL PERFORMANCE CURVES (CONT) TA = +25°C and VS = ±35VDC, unless otherwise noted. DYNAMIC RESPONSE DYNAMIC RESPONSE ZLOAD = ∞, VS = ±35V, AV = +1 ZLOAD = 4700pF, VS = ±35V, AV = +1 INSTALLATION INSTRUCTIONS POWER SUPPLIES pation (total of both amplifiers) times the appropriate thermal resistance— The OPA2541 is specified for operation from power supplies up to ±40V. It can also be operated from an unbalanced or a single power supply so long as the total power supply voltage does not exceed 80V (70V for “AM” grade). The power supplies should be bypassed with low series impedance capacitors such as ceramic or tantalum. These should be located as near as practical to the amplifier’s power supply pins. Good power amplifier circuit layout is, in general, like good high-frequency layout. Consider the path of large power supply and output currents. Avoid routing these connections near low-level input circuitry to avoid waveform distortion and instability. ∆ TJC = (PD total) (θJC). Sufficient heat sinking must be provided to keep the case temperature within safe limits for the maximum ambient temperature and power dissipation. The thermal resistance of the heat sink required may be calculated by: θHS = (150°C – ∆ TJC – TA)/PD. Commercially available heat sinks usually specify thermal resistance. These ratings are often suspect, however, since they depend greatly on the mounting environment and air flow conditions. Actual thermal performance should be verified by measurement of case temperature under the required load and environmental conditions. Signal dependent load current can modulate the power supply voltage with inadequate power supply bypassing. This can affect both amplifiers’ outputs. Since the second amplifier’s signal may not be related to the first, this will degrade the inherent channel separation of the OPA2541. No insulating hardware is required when using the OPA2541. Since mica and other similar insulators typically add 0.7°C/W thermal resistance, this is a significant advantage. See Burr-Brown Application Note AN-83 for further details on heat sinking. HEAT SINKING Most applications will require a heat sink to prevent junction temperatures from exceeding the 150°C maximum rating. The type of heat sink required will depend on the output signals, power dissipation of each amplifier, and ambient temperature. The thermal resistance from junction-to-case, θJC, depends on how the power dissipation is distributed on the amplifier die. SAFE OPERATING AREA The Safe Operating Area (SOA) curve provides comprehensive information on the power handling abilities of the OPA2541. It shows the allowable output current as a function of the voltage across the conducting output transistor (see Figure 1). This voltage is equal to the power supply voltage minus the output voltage. For example, as the amplifier output swings near the positive power supply voltage, the voltage across the output transistor decreases and the device can safely provide large output currents demanded by the load. DC output concentrates the power dissipation in one output transistor. AC output distributes the power dissipation equally between the two output transistors and therefore has lower thermal resistance. Similarly, the power dissipation may be all in one amplifier (worst case) or equally distributed between the two amplifiers (best case). Thermal resistances are provided for each of these possibilities. The case-tojunction temperature rise is the product of the power dissi- ® 5 OPA2541 APPLICATIONS CIRCUITS The internal current limit will not provide short-circuit protection in most applications. When the amplifier output is shorted to ground, the full power supply voltage is impressed across the conducting output transistor. For instance, with VS = ±35V, a short circuit to ground would impress 35V across the conducting power transistor. The maximum safe output current at this voltage is 1.8A, so the internal current limit would not protect the amplifier. The unit-to-unit variation and temperature dependence of the internal current limit suggest that it be used to handle abnormal conditions and not activated in commonly encountered circuit operation. +VS 10µF + 0.1µF D1 L D2 SAFE OPERATING AREA 0.1µF 10 Inductiveor EMFGenerating Load TC = +25°C TC = +85°C 10µF * |IO| (A) + TC = +125°C –VS 1.0 D1 – D2: IN4003 FIGURE 2. Clamping Output for EMF-Generating Loads. *Depending on temperature, maximum output may be restricted by internal current limit. See output current specifications and typical curves. 0.1 1 10 +35V 0.1µF 100 |VS – VOUT| (V) R2 10kΩ FIGURE 1. Safe Operating Area. 30pF Reactive, or EMF generating loads such as DC motors can present demanding SOA requirements. With a purely reactive load, output voltage current occurs when the output voltage is zero and the voltage across the conducting transistor is equal to the full power supply voltage. See BurrBrown Application Note AN-123 for further information on evaluating SOA. VO 0.5Ω VIN R1 2.5kΩ 0.1µF AV = 1 + R2/R1 = 5 –35V Applications with inductive or EMF-generating loads which can produce “kick back” voltage surges to the amplifiers should include clamp diodes from the output terminals to the power supplies. These diodes should be chosen to limit the peak amplifier output voltage surges to less than 2V beyond the power supply rail voltage. Common 1A rated rectifier diodes will suffice in most applications. FIGURE 3. Isolating Capacitive Loads. R2 100kΩ 20pF R1 10kΩ AV = –R2/R1 = –10 VIN 0.1Ω A L 10kΩ Master 20pF 0.1Ω B Slave FIGURE 4. Paralleled Operation, Extended SOA. ® OPA2541 6 +60V 0.1µF 25kΩ 0-2mA DAC80-CBI-I VO 0-50V 0.1µF Protects DAC During Slewing –8V FIGURE 5. Programmable Voltage Source. +15V +35V + + 1µF 1µF Digital Word Input 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 18 23 100pF MSB 0.5Ω 1/2 OPA2541 VOUT = –30V to +30V DAC702 1µF + 21 –35V +15V FB ±1mA 10kΩ 17 + 1µF 10kΩ(1) LSB 7 20 19 + 6 1µF OPA27 2 3 4 –15V + NOTE: (1) TCR Tracking Resistors. 1µF 5kΩ(1) –15V FIGURE 6. 16-Bit Programmable Voltage Source. ® 7 OPA2541 VIN 10kΩ 10kΩ 10kΩ +35V 1/2 OPA2541 1/2 OPA2541 EMF 0.6Ω 0.1Ω –35V 5kΩ INA105KP 5kΩ 5 25kΩ 25kΩ 25kΩ 25kΩ 2 Regulation Adjust 6 1 7 +15V +VS 750mA Continuous (1) L –VS NOTE: (1) Midwest Components Inc. 288D01006 FIGURE 8. Limiting Output Current. ® OPA2541 4 –15V FIGURE 7. Bridge Amplifier Motor-Speed Controller. VIN 10kΩ PMI MOD907 8 3