OPA512 ® Very-High Current—High Power OPERATIONAL AMPLIFIER FEATURES APPLICATIONS ● WIDE SUPPLY RANGE: ±10V to ±50V ● HIGH OUTPUT CURRENT: 15A Peak ● CLASS A/B OUTPUT STAGE: Low Distortion ● ● ● ● ● ● VOLTAGE-CURRENT LIMIT PROTECTION CIRCUIT ● SMALL TO-3 PACKAGE DESCRIPTION The OPA512 is a high voltage, very-high current operational amplifier designed to drive a wide variety of resistive and reactive loads. Its complementary class A/B output stage provides superior performance in applications requiring freedom from cross-over distortion. User-set current limit circuitry provides protection to the amplifier and load in fault conditions. A resistor-programmable voltage-current limiter circuit may be used to further protect the amplifier from damaging conditions. 3 SERVO AMPLIFIER MOTOR DRIVER SYNCRO EXCITATION AUDIO AMPLIFIER TEST PIN DRIVER The OPA512 employs a laser-trimmed monolithic integrated circuit to bias the output transistors, providing excellent low-level signal fidelity and high output voltage swing. The reduced internal parts count made possible with this monolithic IC improves performance and reliability. This hybrid integrated circuit is housed in a hermetic TO-3 package and all circuitry is electrically-isolated from the case. This allows direct mounting to a chassis or heat sink without cumbersome insulating hardware and provides optimum heat transfer. +VS 2 4 5 RCL+ 1 Bias Circuit Out 7 RCL– 8 RVI (Optional) 6 –VS International Airport Industrial Park • Mailing Address: PO Box 11400 Tel: (520) 746-1111 • Twx: 910-952-1111 • Cable: BBRCORP • © 1985 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-600B Printed in U.S.A. December, 1993 SPECIFICATIONS ELECTRICAL At TC = +25°C, and VS = ±40V, unless otherwise noted. OPA512BM PARAMETER CONDITIONS INPUT OFFSET VOLTAGE Initial Offset vs Temperature vs Supply Voltage vs Power INPUT BIAS CURRENT Initial vs Temperature vs Supply Voltage INPUT OFFSET CURRENT Initial vs Temperature MIN Specified Temp. Range Specified Temp. Range Specfied Temp. Range INPUT IMPEDANCE, DC INPUT CAPACITANCE VOLTAGE RANGE Common-Mode Voltage Common-Mode Rejection GAIN Open-Loop Gain at 10Hz Gain-Bandwidth Product, 1MHz Power Bandwidth Phase Margin OUTPUT Voltage Swing (1) Specified Temp. Range Specified Temp. Range 1kΩ Load Specified Temp. Range 8Ω Load 8Ω Load 8Ω Load Specified Temp. Range 8Ω Load BM at 10A, SM at 15A Specified Temp. Range IO = 80mA IO = 5A Current, Peak Settling Time to 0.1% Slew Rate Capacitive Load POWER SUPPLY Voltage Current, Quiescent THERMAL RESISTANCE AC Junction-to-Case(3) DC Junction-to-Case Junction to Air TEMPERATURE RANGE Specified ±(|VS| – 5) 74 MAX TYP MAX UNITS ±2 ±10 ±30 ±20 ±6 ±65 ±200 ±1 * * * ±3 ±40 * mV µV/°C µV/V µV/V 12 ±50 ±10 30 400 10 * * 20 * nA pA/°C pA/V ±12 ±50 ±30 ±5 * ±10 nA pA/°C * MΩ 3 * pF * * V dB * dB * * * dB MHz kHz * Degrees * * 110 96 108 4 20 13 * * 20 ±(|VS| – 6) ±(|VS| – 7) V ±(|VS| – 5) ±(|VS| – 5) 10 * * 15 V V A µs V/µs 2 4 2.5 Specified Temp. Range G=1 Specified Temp. Range G > 10 ±10 TC = –55°C to +125°C, f > 60Hz TC = –55°C to +125°C TC = –55°C to +125°C TC MIN 200 ±(|VS| – 3) 100 2V Step Specified Temp. Range OPA512SM TYP –25 * * * 1.5 * SOA(2) * ±40 25 ±45 50 0.8 1.25 30 0.9 1.4 +85 * –55 nF * * ±50 35 V mA * * * * * °C/W °C/W °C/W +125 °C *Specification same as OPA512BM. NOTES: (1) +VS and –VS denote the postive and negative supply voltage, respectively. Total VS is measured from +VS to –VS. (2) SOA = Safe Operating Area. (3) Rating applies if the output current alternates between both output transistors at a rate faster than 60Hz. 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. ® OPA512 2 ABSOLUTE MAXIMUM RATINGS CONNECTION DIAGRAM Supply Voltage, +VS to –VS ................................................................ 100V Output Current: Source ........................................................................ 15A Sink .................................................................... see SOA Power Dissipation, Internal(1) ............................................................ 125W Input Voltage: Differential ........................................................ ±(|VS| – 3V) Common-mode ............................................................. ±VS Temperature: Pins (soldering, 10s) ................................................ +300°C Junction(1) ............................................................... +200°C Temperature Range: Storage(2) ...................................... –65°C to +150°C Operating (Case) .......................... –55°C to +125°C Top View +RCL +Current Limit +VS 3 2 +In 4 1 –In 5 8 Output –RCL NOTES: (1) Long term operation at the maximum junction temperature will result in reduced product life. Derate internal power dissipation to achieve high MTTF. (2) OPA512BM, –55°C to +100°C. 6 –VS 7 RVI –Current Limit ORDERING INFORMATION MODEL PACKAGE TEMPERATURE RANGE OPA512BM OPA512SM 8-pin TO-3 8-pin TO-3 –25°C to +85°C –55°C to +125°C PACKAGE INFORMATION MODEL PACKAGE PACKAGE DRAWING NUMBER(1) OPA512BM OPA512SM 8-Pin TO-3 8-Pin TO-3 030 030 NOTE: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix D of Burr-Brown IC Data Book. ® 3 OPA512 TYPICAL PERFORMANCE CURVES TA = 25°C, VS = ±40VDC, unless otherwise noted. BIAS CURRENT 2.5 120 2.2 Normalized Bias Current, IB Internal Power Dissipation, P (W) POWER DERATING 140 100 80 60 40 BM SM 20 0 1.9 1.6 1.3 1.0 0.7 0.4 0 20 40 60 80 100 120 140 –50 –25 Case Temperature, TC (°C) 15.0 100 VO = 0 RCL = 0.06Ω, RVI = ∞ 10.0 7.5 VO = 24V 5.0 RCL = 0.18Ω, RVI = 0 VO = 0 25 50 75 100 125 1M 10M SMALL SIGNAL RESPONSE 120 Open-Loop Gain, A (dB) Current Limit, ILIM (A) CURRENT LIMIT 17.5 12.5 0 Case Temperature, TC (°C) 2.5 80 60 40 20 0 VO = –24V 0 –20 –50 –25 0 25 50 75 100 125 1 10 100 1k Case Temperature, TC (°C) PHASE RESPONSE 100k POWER RESPONSE 0 100 –30 68 Output Voltage, VO (Vp-p) Phase, φ (degrees) 10k Frequency, f (Hz) –60 –90 –120 –150 –180 |+VS| + |–VS| = 100V |+VS| + |–VS| = 80V 46 32 22 |+VS| + |–VS| = 30V 15 10 6.8 –210 4.6 1 10 100 1k 10k 100k 1M 10M 10 Frequency, f (Hz) 30 Frequency, f (kHz) ® OPA512 20 4 50 70 100 TYPICAL PERFORMANCE CURVES (CONT) TA = 25°C, VS = ±40VDC, unless otherwise noted. PULSE RESPONSE COMMON-MODE REJECTION 8 VIN = ±5V, tR = 100ns 6 100 Output Voltage, VO (V) Common-Mode Rejection, CMR (dB) 120 80 60 40 20 4 2 0 –2 –4 –6 –8 0 1 10 100 1k 10k 100k 0 1M 2 4 8 12 10 HARMONIC DISTORTION 100 3 70 1 50 Distortion (%) Input Noise Voltage, VN (nV/√Hz) INPUT NOISE 40 30 20 G = 10 VS = ±37V RL = 4Ω 0.3 PO = 4W PO = 100mW 0.1 0.03 PO = 120W 0.01 0.003 10 0 100 1k 100 100k 10k 300 1k 3k 10k 30k 100k Frequency, f (Hz) Frequency, f (Hz) QUIESCENT CURRENT OUTPUT VOLTAGE SWING 1.6 Voltage Drop From Supply (V) 6 1.4 Normalized, IQ 6 Time, t (µs) Frequency, f (Hz) TC = –25°C 1.2 TC = +25°C 1.0 TC = +85°C 0.8 TC = +125°C 0.6 0.4 5 4 –VO 3 +VO 2 1 40 50 60 70 80 90 100 0 Total Supply Voltage, VS (V) 3 6 9 12 15 Output Current, IO (A) ® 5 OPA512 APPLICATIONS INFORMATION POWER SUPPLIES 15 Output Current (A) Specifications for the OPA512 are based on a nominal operating voltage of ±40V. A single power supply or unbalanced supplies may be used as long as the maximum total operating voltage (total of +VS and –VS) is not greater than 90V (100V for OPA512SM model.) CURRENT LIMITS Current limit resistors must be provided for proper operation. Independent positive and negative current limit values may be selected by choice of RCL+ and RCL–, respectively. Resistor values are calculated by: Thermal Limit t = 5ms t = 1ms 10 8 6 5 4 3 t = 0.5ms TC = +125°C TC = +25°C 2 1.5 TC = +85°C 1 0.8 0.5 0.4 0.3 0.2 Secondary Breakdown 5 6 7 8 9 10 15 20 40 60 80 100 Voltage Across Output Transistor (V) RCL = 0.65/ILIM (amps) –0.007 FIGURE 1. Safe Operating Area. This is the nominal current limit value at room temperature. The maximum output current decreases at high temperature as shown in the typical performance curve. Most wirewound resistors are satisfactory, but some highly inductive types may cause loop stability problems. Be sure to evaluate performance with the actual resistors to be used in production. under normal load conditions. Sensing both the output current and the output voltage, this limiter circuit increases the current limit value as the output voltage approaches the power supply voltage (where power dissipation is low.) This type of limiting is achieved by connecting pin 7 through a programming resistor to ground. The V-I limiter circuit is governed by the equation: HEAT SINKING Power amplifiers are rated by case temperature (not ambient temperature.) The maximum allowable power dissipation is a function of the case temperature as shown in the power derating curve. Load characteristics, signal conditions, and power supply voltage determine the power dissipated by the amplifier. The case temperature will be determined by the heat sinking conditions. Sufficient heat sinking must be provided to keep the case temperature within safe bounds given the power dissipated and ambient temperature. See Application Bulletin AB-038 for further details. 0.65 + ILIMIT = 0.28 VO 20 + RVI RCL + 0.007 where: ILIMIT is the maximum current available at a given output voltage. RVI is the value (kΩ) of the resistor from pin 7 to ground. RCL is the current limit resistor in ohms. VO is the instantaneous output voltage in volts. SAFE OPERATING AREA (SOA) Reactive or EMF-generating loads may produce unusual (perhaps undesirable) waveforms with the V-I limit circuit driven into limit. Since current peaks in a reactive load do not align with the output voltage peaks, the output waveform will not appear as a simple voltage-limited waveform. Response of the load to the limiter, in fact, may produce a “backfire” reaction producing unusual output waveforms. The safe area plot provides a comprehensive summary of the power handling limitations of a power amplifier, including maximum current, voltage and power as well as the secondary breakdown region (see Figure 1) It shows the allowable output current as a function of the power supply to output voltage differential (voltage across the conducting power device.) See Application Bulletin AB-039 for details on SOA. VOLTAGE-CURRENT LIMITER CIRCUITRY The voltage-current (V-I) limiter circuit provides a means to protect the amplifier from SOA damage such as a short circuit to ground, yet allows high output currents to flow ® OPA512 6