MSA260KC

MSA260 MSA260 MSA260 Pulse Width Modulation Amplifier FEATURES GENERAL DESCRIPTION The MSA260 is a surface mount constructed PWM amplifier that provides a cost effective solution in many industrial applications. The MSA260 offers outstanding performance that rivals many much more expensive hybrid components. The MSA260 is a complete PWM amplifier including an oscillator, comparator, error amplifier, current limit comparators, 5V reference, a smart controller and a full bridge IGBT output circuit. The switching frequency is user programmable up to 50 kHz. The MSA260 is built on a thermally conductive but electrically insulating substrate that can be mounted to a heatsink. • LOW COST • HIGH VOLTAGE - 450 VOLTS • HIGH OUTPUT CURRENT - 20 AMPS • 9kW OUTPUT CAPABILITY • VARIABLE SWITCHING FREQUENCY • IGBT FULL BRIDGE OUTPUT APPLICATIONS • BRUSH MOTOR CONTROL • MRI • MAGNETIC BEARINGS • CLASS D SWITCHMODE AMPLIFIER EQUIVALENT CIRCUIT DIAGRAM VCC 29 5V REF OUT 19 SIGNAL GND 26 2 SIGNAL GND SIGNAL GND 23 DIGITAL RETURN 18 ILIM B 5V REF 7 30-34 +Vs ROSC 22 CLK OUT Q2 + 35-39 - 2.68K 2200pF Q1 - 1K 10 +Vs + 1K .01µF ILIM A/ SHDN 44-48 200mV A OUT SMART CONTROLLER .01µF Q3 OSC 49-53 24 B OUT Q4 E/A OUT 17 E/A -IN 16 - E/A +IN 15 + +IN 13 RRAMP IN 20 CLK IN 21 AC BACK PLATE 28 APEX TP 27 PWR GND 58 www.apexanalog.com MSA260U I SENSE B R2 + R3 5.36K 1 CLK/2 OUT 54-57 40-43 I SENSE A - 2200pF CLK/2 BACK PLATE 1µF Copyright © Apex Microtechnology, Inc. 2014 (All Rights Reserved) JUL 2014 1 MSA260U REVF MSA260 CHARACTERISTICS AND SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS Parameter Symbol Min Max Units SUPPLY VOLTAGE VS 450 V SUPPLY VOLTAGE VCC 16 V OUTPUT CURRENT, peak, within SOA POWER DISSIPATION, internal, DC (Note 3) SIGNAL INPUT VOLTAGES TEMPERATURE, pin solder, 10s TEMPERATURE, junction (Note 2) 30 A 250 W 5.4 V 225 °C 150 °C TEMPERATURE RANGE, storage −40 105 °C OPERATING TEMPERATURE, case −40 85 °C SPECIFICATIONS Parameter Test Conditions (Note 1) Min Typ Max Units Full temperature range 9 mV ERROR AMPLIFIER OFFSET VOLTAGE BIAS CURRENT, initial Full temperature range 500 nA OFFSET CURRENT, initial (Note 3) Full temperature range 150 nA COMMON MODE VOLTAGE RANGE, pos. Full temperature range 4 V SLEW RATE Full temperature range 1 V/µs OPEN LOOP GAIN RL = 2KΩ 96 dB 1 MHz 0 UNITY GAIN BANDWIDTH CLOCK LOW LEVEL OUTPUT VOLTAGE Full temperature range HIGH LEVEL OUTPUT VOLTAGE Full temperature range 0.2 4.8 V V RISE TIME 7 nS FALL TIME 7 nS BIAS CURRENT, pin 22 Full temperature range 0.6 µA 5.15 V 2 mA 2.25 V 5V REFERENCE OUTPUT VOLTAGE 4.85 LOAD CURRENT OUTPUT (Note 4) VCE(ON), each active IGBT ICE = 15A CURRENT, continuous VS = 400V, F = 22kHz 20 A CURRENT, peak 1mS, VS = 400V, F = 22kHz 30 A FLYBACK DIODE CONTINUOUS CURRENT FORWARD VOLTAGE IF = 15A REVERSE RECOVERY IF = 15A 2 0.2 44 20 A 200 1.5 V 0.7 150 nS MSA260U MSA260 Parameter Test Conditions (Note 1) Min Typ Max Units 5 400 450 V 14 15 16 V 9 28 mA 18 mA 10 mA 1 °C/W 14 °C/W 85 °C POWER SUPPLY VOLTAGE, VS VOLTAGE, VCC CURRENT, VS, quiescent 22kHz switching CURRENT, VCC, quiescent 22kHz switching CURRENT, VCC, shutdown THERMAL RESISTANCE, DC, junction to case Full temperature range RESISTANCE, junction to air Full temperature range TEMPERATURE RANGE, case -40 50 EACH ACTIVE COMPONENT 25 0 20 40 60 80 100 CASE TEMPERATURE, (C) REVERSE DIODE TJ = 125 C 16 12 8 4 0 0.4 0.6 0.8 1.0 SOURCE TO DRAIN DIODE VOLTAGE 25 99 98 FREQUENCY = 44KHz 97 1M 100K 10K CLOCK LOAD RESISTANCE, () TC 3 5 = 99.4 99.2 -40 -20 0 20 40 60 80 100 CASE TEMPERATURE, (C) 85 TC 5C =2 2 4 8 12 16 OUTPUT CURRENT, (A) 20 VCC QUIESCENT CURRENT DUTY CYCLE VS. ANALOG INPUT 100 DUTY CYCLE, (%) CONTINUOUS AMPS 10 MSA260U 99.6 C A OUT 15 99.8 TOTAL VOLTAGE DROP 4 1 0 CONTINUOUS OUTPUT 20 CLOCK FREQUENCY OVER TEMP. 100.2 100.0 5 TOTAL VOLTAGE DROP, (V) 0 CLOCK LOADING NORMALIZED FREQUENCY, (%) 75 100 80 60 40 20 B OUT QUIESCENT CURRENT, (mA) 100 20 FLYBACK CURRENT, ISD (A) NORMALIZED FREQUENCY, (%) POWER DERATING 125 TJ = 25C INTERNAL POWER DISSIPATION, (W) NOTES: 1. Unless otherwise noted: TC=25°C, VCC = 15V, VS = 400V, F = 22kHz. 2. Long term operation at the maximum junction temperature will result in reduced product life. Derate internal power dissipation to achieve high MTBF. 3. Each of the two output transistors on at any one time can dissipate 125W. 4. Maximum specification guaranteed but not tested. 24 20 16 12 8 3 50% DUTY CYCLE TOTAL VOLTAGE D 4 MSA260 TC 3 85 TC 5C =2 2 0 0.4 0.6 0.8 1.0 SOURCE TO DRAIN DIODE VOLTAGE 1 0 4 8 12 16 OUTPUT CURRENT, (A) 20 VCC QUIESCENT CURRENT DUTY CYCLE VS. ANALOG INPUT CONTINUOUS OUTPUT 25 = 100 80 DUTY CYCLE, (%) CONTINUOUS AMPS A OUT 20 15 10 60 40 20 5 B OUT 0 1.5 100 2.5 3.0 16 12 8 10 101 100 99 NORMAL or SHUTDOWN OPERATION 97 -40 -20 0 20 40 60 80 100 CASE TEMPERATURE, (C) VS QUIESCENT CURRENT VS QUIESCENT CURRENT vs. FREQUENCY 8 6 4 F = 22kHz, 50% DUTY CYCLE 2 0 100 200 300 VS, (V) 400 50% DUTY CYCLE 4 0 10 20 30 40 50 SWITCHING FREQUENCY, F (kHz) 3.5 ANALOG INPUT, (V) VCC QUIESCENT CURRENT 98 2.0 20 24 VS QUIESCENT CURRENT, IQ (mA) 102 25 50 75 CASE TEMPERATURE, (C) VS QUIESCENT CURRENT, (mA) NORMALIZED QUIESCENT CURRENT, (%) 0 0 24 VCC QUIESCENT CURRENT, (mA) 8 TJ = 25C TJ = 125 C FLYBACK CURREN 12 500 20 16 12 8 VS = 400V, 50% DUTY CYCLE 4 0 0 10 20 30 40 50 SWITCHING FREQUENCY, F (kHz) 10 11 12 13 14 15 16 17 18 19 NC SIG GND APEX TP AC BACK PLATE CLK OUT DIG RTN CLK/2 OUT CLK IN ROSC SIG GND +5V OUT EA -IN EA OUT NC EA +IN +IN 9 NC 8 NC 7 ILIM A/SHDN 6 NC 5 ILIM B 4 NC 3 NC NC 2 NC SIG GND 1 NC RRAMP IN EXTERNAL CONNECTIONS 20 21 22 23 24 25 26 27 28 RRAMP VIEW FROM COMPONENT SIDE C1 58 PWR GND 4 ROSC C2 + C3 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 ISENSE B B OUT +Vs SINGLE POINT GND ISENSE A A OUT 35 34 33 32 31 +Vs 30 29 VCC NOTES: C2 IS ELECTROLYTIC ≥10UF PER AMP OUTPUT CURRENT C1,3 HIGH QUALITY CERAMIC ≥1.0UF ALL +Vs MUST BE TIED TOGETHER ALL SIG GND PINS MUST BE TIED TOGETHER SINGLE POINT GROUND @ PIN 26 MSA260U MSA260 58-pin DIP PACKAGE STYLE KC TYPICAL APPLICATION TORQUE MOTOR CONTROL With the addition of a few external components the MSA260 becomes a motor torque controller. In the MSA260 the source terminal of each low side IGBT driver is brought out for current sensing via RSA and RSB. A1 is a differential amplifier that amplifies the difference in currents of the two half bridges. This signal is fed into the internal error amplifier that mixes the current signal and the control signal. The result is an input signal to the MSA260 that controls the torque on the motor. SINGLE POINT GND @ 26 20 RRAMP 58 2,18,26 28 23 SIG DIG PWR AC GND RET GND BACK PLATE CLK/2 OUT 1 RRAMP IN 21 CLK IN 24 CLK OUT ROSC 22 ROSC A OUT 35-39 PWM AMPLIFIER 19 +5V REF OUT 13 +IN 17 E/A OUT B OUT 49-53 16 E/A -IN 15 E/A +IN CONTROL SIGNAL Is B Is A 54-57 2.5V 40-43 A1 Rs A Rs B 2.5V GENERAL Please read Application Note 30 “PWM Basics”. Refer also to Application Note 1 “General Operating Considerations” for helpful information regarding power supplies, heat sinking, mounting, SOA interpretation, and specification interpretation. Visit www.apexanalog.com for design tools that help automate tasks such as calculations for stability, internal power dissipation, current limit, heat sink selection, Apex Microtechnology’s complete Application Notes library, Technical Seminar Workbook and Evaluation Kits. MSA260U 5 MSA260 OSCILLATOR The MSA260 includes a user frequency programmable oscillator. The oscillator determines the switching frequency of the amplifier. The switching frequency of the amplifier is 1/2 the oscillator frequency. Two resistor values must be chosen to properly program the switching frequency of the amplifier. One resistor, ROSC, sets the oscillator frequency. The other resistor, RRAMP, sets the ramp amplitude. In all cases the ramp voltage will oscillate between 1.5V and 3.5V. See Figure 1. If an external oscillator is applied use the equations to calculate RRAMP . RRAMP = 2 X ROSC Use 1% resistors with 100ppm drift (RN55C type resistors, for example). Maximum switching frequency is 50kHz. PWR GND 58 10 7 Isense B where F is the desired switching frequency and: Isense A ROSC = (1.32X108 / F) - 2680 IlimB PWM AMPLIFIER IlimA/SHDN To program the oscillator, ROSC is given by: 40-43 R 54-57 C 9R R Example: C If the desired switching frequency is 22kHz then ROSC = Rs A Rs B 5V SHDN 3.32K and RRAMP = 6.64K. Choose the closest standard 1% SIGNAL values: ROSC = 3.32K and RRAMP = 6.65K or simply use two of selected ROSC in series for RRAMP. FIGURE 1. EXTERNAL OSCILLATOR CONNECTIONS 21 20 CLK/2 OUT 24 CLK IN 22 RRAMP CLK OUT CURRENT SENSING ROSC ROSC The MSA260 output stage can be turned off with a shutdown command voltage applied to Pin 10 as shown in Figure 2. The shutdown signal is OR’ed with the current limit signal and simply overrides it. As long as the shutdown signal remains high the output will be off. 1 RRAMP IN SHUTDOWN The low side drive transistors of the MSA260 are brought out for sensing the PWM AMPLIFIER current in each half bridge. A resistor from each sense line to PWR GND (pin 58) develops the current sense voltage. Choose R and C such that the time FIGURE 2. CURRENT LIMIT WITH constant is equal to 10 periods of the selected switching frequency. The in- OPTIONAL SHUTDOWN ternal current limit comparators trip at 200mV. Therefore, current limit occurs at I = 0.2/RSENSE for each half bridge. See Figure 2. Accurate milliohm power resistors are required and there are several sources for these listed in the Accessories Vendors section of the Databook. POWER SUPPLY BYPASSING Bypass capacitors to power supply terminals +VS must be connected physically close to the pins to prevent local parasitic oscillation and overshoot. All +VS must be connected together. Place and electrolytic capacitor of at least 10µF per output amp required midpoint between these sets of pins. In addition place a ceramic capacitor 1.0µF or greater directly at each set of pins for high frequency bypassing. VCC is bypassed internally. GROUNDING AND PCB LAYOUT Switching amplifiers combine millivolt level analog signals and large amplitude switching voltages and currents with fast rise times. As such grounding is crucial. Use a single point ground at SIG GND (pin 26). Connect signal ground pins 2 and 18 directly to the single point ground on pin 26. Connect the digital return pin 23 directly to pin 26 as well. Connect PWR GND pin 58 also to pin 26. Connect AC BACKPLATE pin 28 also to the single point ground at pin 26. Connect the ground terminal of the VCC supply directly to pin 26 as well. Make sure no current from the load return to PWR GND flows in the analog signal ground. Make sure that the power portion of the PCB layout does not pass over low-level analog signal traces on the opposite side of the PCB. Capacitive coupling through the PCB may inject switching voltages into the analog signal path. Further, make sure that the power side of the PCB layout does not come close to the analog signal side. Fast rising output signal can couple through the trace-to-trace capacitance on the same side of the PCB. 6 MSA260U MSA260 DETERMINING THE OUTPUT STATE The input signal is applied to +IN (Pin 13) and varies from 1.5 to 3.5 volts, zero to full scale. The ramp also varies over the same range. When: Ramp > +IN AOUT > BOUT The output duty cycle extremes vary somewhat with switching frequency and are internally limited to approximately 5% to 95% at 10kHz and 7% to 93% at 50kHz. CALCULATING INTERNAL POWER DISSIPATION Detailed calculation of internal power dissipation is complex but can be approximated with simple equations. Conduction loss is given by: W = I • 2.5 + I2 • 0.095 where I = output current Switching loss is given by: W = 0.00046 • I • Vsupply • Fswitching (in kHz) Combine these two losses to obtain total loss. Calculate heatsink ratings and case temperatures as would be done for a linear amplifier. For calculation of junction temperatures, assume half the loss is dissipated in each of two switches: Tj = Ta + Wtotal • RØhs + 1/2Wtotal • RØjc, where: RØhs = heatsink rating RØjc = junction-to-case thermal resistance of the MSA260. The SOA typical performance graphs below show performance with the MSA260 mounted with thermal grease on the Apex Microtechnology HS26. The Free Air graph assumes vertical orientation of the heatsink and no obstruction to air flow in an ambient temperature of 30°C. The other two graphs show performance with two levels of forced air. Note that air velocity is given in linear feet per minute. As fans are rated in cubic delivery capability, divide the cubic rating by the square area this air flows through to find velocity. As fan delivery varies with static pressure, these calculations are approximations, and heatsink ratings vary with amount of power dissipated, there is no substitute for temperature measurements on the heatsink in the center of the amplifier footprint as a final check. SOA, HS26, FREE AIR SOA, HS26, 150LFM FORCED AIR 150 Vs =2 Vs 50 Vs =3 =4 50 50 18 16 14 MSA260U Vs=350 12 10 7 5 10 15 20 25 30 35 40 45 50 SWITCHING FREQUENCY, KHz Vs=250 Vs=450 5 10 15 20 25 30 35 40 45 50 SWITCHING FREQUENCY, KHz 19 OUTPUT CURRENT, A Vs= 16 10 20 Vs=150 OUTPUT CURRENT, A OUTPUT CURRENT, A 19 13 SOA, HS26, 500LFM FORCED AIR 20 Vs=250 18 17 Vs=350 16 15 Vs=450 14 13 12 15 20 25 30 35 40 45 50 SWITCHING FREQUENCY, KHz 7 MSA260 NEED TECHNICAL HELP? CONTACT APEX SUPPORT! For all Apex Microtechnology product questions and inquiries, call toll free 800-546-2739 in North America. For inquiries via email, please contact apex.support@apexanalog.com. International customers can also request support by contacting their local Apex Microtechnology Sales Representative. To find the one nearest to you, go to www.apexanalog.com IMPORTANT NOTICE Apex Microtechnology, Inc. has made every effort to insure the accuracy of the content contained in this document. However, the information is subject to change without notice and is provided "AS IS" without warranty of any kind (expressed or implied). Apex Microtechnology reserves the right to make changes without further notice to any specifications or products mentioned herein to improve reliability. This document is the property of Apex Microtechnology and by furnishing this information, Apex Microtechnology grants no license, expressed or implied under any patents, mask work rights, copyrights, trademarks, trade secrets or other intellectual property rights. Apex Microtechnology owns the copyrights associated with the information contained herein and gives consent for copies to be made of the information only for use within your organization with respect to Apex Microtechnology integrated circuits or other products of Apex Microtechnology. This consent does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale. APEX MICROTECHNOLOGY PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN PRODUCTS USED FOR LIFE SUPPORT, AUTOMOTIVE SAFETY, SECURITY DEVICES, OR OTHER CRITICAL APPLICATIONS. PRODUCTS IN SUCH APPLICATIONS ARE UNDERSTOOD TO BE FULLY AT THE CUSTOMER OR THE CUSTOMER’S RISK. Apex Microtechnology, Apex and Apex Precision Power are trademarks of Apex Microtechnolgy, Inc. All other corporate names noted herein may be trademarks of their respective holders. www.apexanalog.com 8 Copyright © Apex Microtechnology, Inc. 2014 (All Rights Reserved) JUL 2014 MSA260U MSA260U REVF