HIGH VOLTAGE POWER OPERATIONAL AMPLIFIER PA97 HTTP://WWW.APEXMICROTECH.COM M I C R O T E C H N O L O G Y (800) 546-APEX (800) 546-2739 FEATURES • HIGH VOLTAGE — 900V (±450V) • LOW QUIESCENT CURRENT — 600µA • HIGH OUTPUT CURRENT — 10mA APPLICATIONS • • • • • MASS SPECTROMETERS SCANNING COILS HIGH VOLTAGE INSTRUMENTATION PROGRAMMABLE POWER SUPPLIES UP TO 880V SEMICONDUCTOR MEASUREMENT EQUIPMENT PATENT PENDING TYPICAL APPLICATION DESCRIPTION The PA97 is a high voltage MOSFET operational amplifier designed as a low cost solution for driving continuous output currents up to 10mA and pulse currents to 15mA into capacitive loads. The safe operating area (SOA) has no second breakdown limitations. The MOSFET output stage is biased class C for low quiescent current operation. External compensation provides flexibility in choosing bandwidth and slew rate for the application. APEX’s SIP05 package uses a minimum of board space allowing for high density circuit boards. EQUIVALENT SCHEMATIC +VS R IN PIEZO DRIVE R1 R2 Q1 C1 COMPUTER FOCUS COMMAND VOLTAGE LOW POWER, PIEZOELECTRIC POSITIONING R3 Q3 Q2 R4 Q4 Q6 4 CC1 Q5 6 CC2 8 OUT Q7 Q6 R8 Q10 2 +IN Piezo positioning may be applied to the focusing of segmented mirror systems. The composite mirror may be composed of hundreds of elements, each requiring focusing under computer control. In such complex systems the PA97 reduces the costs of power supplies and cooling with its advantages of low cost and low quiescent power consumption while increasing circuit density with the SIP package. EXTERNAL CONNECTIONS R6 R5 R7 –IN +IN CC1 CC2 1 2 4 6 R9 C c* Q9 Q8 R10 –VS 10 V OUT PA97 –V S 12 +VS 1 –IN RF R11 PACKAGE: SIP05 OUT 8 –Vs +Vs 10 12 * * * .01µF or greater ceramic power supply bypassing required. Cc =10pF minimum, 1kV NPO(COG) PHASE COMPENSATION GAIN ≥ 10 CC 10pF APEX MICROTECHNOLOGY CORPORATION • TELEPHONE (520) 690-8600 • FAX (520) 888-3329 • ORDERS (520) 690-8601 • EMAIL [email protected] ABSOLUTE MAXIMUM RATINGS SPECIFICATIONS PA97 SUPPLY VOLTAGE, +VS to –VS OUTPUT CURRENT, source, sink POWER DISSIPATION, continuous @ TC = 25°C INPUT VOLTAGE, differential3 INPUT VOLTAGE, common mode (See Text) TEMPERATURE, pin solder - 10s max TEMPERATURE, junction2 TEMPERATURE, storage OPERATING TEMPERATURE RANGE, case ABSOLUTE MAXIMUM RATINGS 900V 15mA, within SOA 5W ±20V ±VS 220°C 150°C –65 to +150°C –55 to +125°C SPECIFICATIONS TEST CONDITIONS 1 PARAMETER MIN TYP MAX UNITS .5 10 10 75 200 4 50 1011 4 5 50 25 98 2 mV µV/°C µV/V µV/√kh pA pA/V pA Ω pF V dB µVrms 94 111 1 2 60 dB MHz kHz ° ±VS 24 10 ±VS 20 V mA V/µs µs Ω INPUT Full temperature range VS=±250V See Note 3 VCM = ±90V 10KHz BW, RS = 1KΩ, CC = 10pF ±VS 30 80 ± OFFSET VOLTAGE, initial OFFSET VOLTAGE, vs. temperature OFFSET VOLTAGE, vs. supply OFFSET VOLTAGE, vs. time BIAS CURRENT, initial BIAS CURRENT, vs. supply OFFSET CURRENT, initial INPUT IMPEDANCE, DC INPUT CAPACITANCE COMMON MODE VOLTAGE RANGE3 COMMON MODE REJECTION, DC NOISE 2000 500 GAIN OPEN LOOP, @ 15Hz GAIN BANDWIDTH PRODUCT at 1MHz POWER BANDWIDTH PHASE MARGIN, AV = 100 RL = 5KΩ, CC = 10pF RL = 5KΩ, CC = 10pF RL = 5KΩ, CC = 10pF Full temperature range OUTPUT ± IO = 10mA CC = 10pF CC = 10pF, 2V step 10mA Load ± VOLTAGE SWING3 CURRENT, continuous SLEW RATE, AV = 100 SETTLING TIME to .1% RESISTANCE 8 2 100 POWER SUPPLY VOLTAGE 5 CURRENT, quiescent, See note 5 ±50 ±300 .6 ±450 1 V mA 20 25 °C/W °C/W °C/W °C THERMAL RESISTANCE, AC, junction to case 4 RESISTANCE, DC, junction to case RESISTANCE, junction to air TEMPERATURE RANGE, case NOTES: 1. 2. 3. 4. 5. CAUTION Full temperature range, F > 60Hz Full temperature range, F < 60Hz Full temperature range 40 –25 +85 Unless otherwise noted: TC = 25°C, DC input specifications are ± value given. Power supply voltage is typical rating. CC = 10pF. Long term operation at the maximum junction temperature will result in reduced product life. Derate internal power dissipation to achieve high MTTF. Although supply voltages can range up to ± 450V the input pins cannot swing over this range. The input pins must be at least 30V from either supply rail but not more than 500V from either supply rail. See text for a more complete description of the common mode voltage range. Rating applies if the output current alternates between both output transistors at a rate faster than 60Hz. Derate max supply rating .625 V/°C below 25°C case. No derating needed above 25°C case. The PA97 is constructed from MOSFET transistors. ESD handling procedures must be observed. APEX MICROTECHNOLOGY CORPORATION • 5980 NORTH SHANNON ROAD • TUCSON, ARIZONA 85741 • USA • APPLICATIONS HOTLINE: 1 (800) 546-2739 PA97 -140 3 2 1 0 140 25 50 75 100 125 150 TEMPERATURE, T (°C) SMALL SIGNAL RESPONSE OPEN LOOP GAIN, A (dB) 120 100 OUTPUT CURRENT FROM +VS OR –VS, (mA) -180 -200 0 C 80 C = 10 pF 60 40 20 0 -160 1 10 100 1K 10K .1M 1M 10M FREQUENCY, F (Hz) SAFE OPERATING AREA 20 10 DC 10 8 6 5 4 3 ,T DC ,T DC 0µ S C= 25 C= °C 85 ,T C= 12 °C 5° C 2 CC=10pF 1 200 300 400 600 100 1000 SUPPLY TO OUTPUT DIFFERENTIAL, VS –VO (V) -220 .6M 1M 2M FREQUENCY, F (Hz) 3M SWING FROM +VS 13 12 11 10 SWING FROM -VS 9 0 2 4 6 8 10 OUTPUT CURRENT, I O (mA) 1.08 QUIESCENT CURRENT 1.04 1.00 0.96 0.92 0.88 100 200 300 400 500 600 700 800 900 TOTAL SUPPLY VOLTAGE, VSs (V) POWER RESPONSE OUTPUT VOLTAGE SWING 1K 14 OUTPUT VOLTAGE, VO (VP-P) PHASE,φ (°) 4 NORMALIZED QUIESCENT CURRENT, I(X) -120 500 C C = 10pF 200 100 50 1K INPUT NOISE VOLTAGE, VN (nV/ ÷ Hz) PHASE RESPONSE POWER DERATING 5 VOLTAGE DROP FROM SUPPLY, V S – VO (V) INTERNAL POWER DISSIPATION, P(W) TYPICAL PERFORMANCE GRAPHS 20 10K FREQUENCY, F (Hz) 30K INPUT NOISE 15 10 7 5 3 2 10 100 1K 10K FREQUENCY, F (Hz) 1M APEX MICROTECHNOLOGY CORPORATION • TELEPHONE (520) 690-8600 • FAX (520) 888-3329 • ORDERS (520) 690-8601 • EMAIL [email protected] OPERATING CONSIDERATIONS PA97 GENERAL Please read the “General Operating Considerations” section, which covers stability, supplies, heatsinking, mounting, current limit, SOA interpretation, and specification interpretation. Additional information can be found in the application notes. For information on the package outline, heatsinks, and mounting hardware, consult the “Accessory and Package Mechanical Data” section of the handbook. CURRENT LIMIT The PA97 has no provision for current limiting the output. COMMON MODE INPUT RANGE Operational amplifiers are usually designed to have a common mode input voltage range that approximates the power supply voltage range. However, to keep the cost as low as possible and still meet the requirements of most applications the common mode input voltage range of the PA97 is restricted. The input pins must always be a least 30V from either supply voltage but never more than 500V. This means that the PA97 cannot be used in applications where the supply voltages are extremely unbalanced. For example, supply voltages of +800V and –100V would not be allowed in an application where the non-inverting pin is grounded because in normal operation both input pins would be at 0V and the difference voltage between the positive supply and the input pins would be 800V. In this kind of application, however, supply voltages +500V and -100V does meet the input common mode voltage range requirements since the maximum difference voltage between the inputs pins and the supply voltage is 500V (the maximum allowed). The output has no such restrictions on its voltage swing. The output can swing within 24V of either supply voltage regardless of value so long as the total supply voltage does not exceed 900V. INPUT PROTECTION Although the PA97 can withstand differential input voltages up to ±20V, additional external protection is recommended. In most applications 1N4148 or 1N914 signal diodes are sufficient (D1, D2 in Figure 2a). In more demanding applications where low leakage or low capacitance are of concern 2N4416 or 2N5457-2N5459 JFETs connected as diodes will be required (Q1, Q2 in Figure 2b). In either case the input differential voltage will be clamped to ±.7V. This is sufficient overdrive to produce maximum power bandwidth. Note that this protection does not automatically protect the amplifier from excessive common mode input voltages. POWER SUPPLY PROTECTION Unidirectional zener diode transient suppressors are recommended as protection on the supply pins. The zeners clamp transients to voltages within the power supply rating and also clamp power supply reversals to ground. Whether the zeners are used or not, the system power supply should be evaluated for transient performance including power-on overshoot and power-off polarity reversal as well as line regulation. Conditions which can cause open circuits or polarity reversals on either power supply rail should be avoided or protected against. Reversals or opens on the negative supply rail is known to induce input stage failure. Unidirectional transzorbs prevent this, and it is desirable that they be both electrically and physically as close to the amplifier as possible. EXTERNAL COMPONENTS The compensation capacitor Cc must be rated for the total supply voltage. 10pF NPO (COG)capacitor rated at 1kV is recommended. Of equal importance is the voltage rating and voltage coefficient of the gain setting feedback resistor. Typical voltage ratings of low wattage resistors are 150 to 250V. Up to 900 V can appear across the feedback resistor. High voltage rated resistors can be obtained. However a 1 megohm feedback resistor composed of five 200k resistors in series will produce the proper voltage rating. CAUTIONS The operating voltages of the PA97 are potentially lethal. During circuit design develop a functioning circuit at the lowest possible voltages. Clip test leads should be used for "hands off" measurements while troubleshooting. With no internal current limit, proper choice of load impedance and supply voltage is required to meed SOA limitiations. An output short circuit will destroy the amplifier within milliseconds. STABILITY The PA97 is stable at gains of 10 or more with a NPO (COG) compensation capacitor of 10pF. The compensation capacitor, Cc, in the external connections diagram must be rated at 1000V working voltage and mounted closely to pins 4 and 6 to prevent spurious oscillation. A compensation capacitor less than 10pF is not recommended. +VS Z1 A. –IN D1 +IN 1 12 D2 PA97 2 10 Z2 –VS B. +VS Z1 –IN Q1 +IN 1 12 Q2 PA97 2 10 Z2 –VS This data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible inaccuracies or omissions. All specifications are subject to change without notice. PA97U REV. B AUGUST 2000 © 2000 Apex Microtechnology Corp.