4707 dey road liverpool, n.y. 13088 (315) 701-6751 m.s.kennedy corp. mil-prf-38534 certified 4460 10 amp, 55v, 3 phase mosfet brushless motor controller equivalent schematic description: the msk 4460 is a complete 3 phase mosfet bridge brushless motor control system in an electrically isolated low cost package. the hybrid is capable of 10 amps of output current and 55 volts of dc bus voltage. it has the normal features for protecting the bridge. included is all the bridge drive circuitry, hall sensing circuitry, commutation circuitry and all the current sensing and analog circuitry necessary for closed loop current mode (torque) control. when pwm'ing, the transistors are modulated in locked anti-phase mode for the tightest control and the most bandwidth. provisions for applying different compensation schemes are included. the msk 4460 has good thermal conductivity of the mosfet's due to isolated substrate/package design that allows direct heat sinking of the hybrid without insulators. features: 55 volt motor supply voltage 10 amp output switch capability 100% duty cycle high side conduction capable shoot-through/cross conduction protection hall sensing and commutation circuitry on board internal 15 volt regulators "real" four quadrant torque control capability good accuracy around the null torque point non-hermetic isolated package for high voltage isolation typical applications 3 phase brushless dc motor control servo control fin actuator control gimbal control az-el control rev. g 1/11 1 pin-out information 1 2 3 4 5 6 7 8 9 10 +15v l1 nc -15v dis hall c hall b hall a e/a- sig gnd 20 19 18 17 16 15 14 13 12 11 v+ motor drive c motor drive b motor drive a v+ rtn +current command -current command current monitor e/a out nc
55v 0.16a 13.5v 20ma 20ma 10a 16a high voltage supply v+ quiescent current current command input output current output current continuous output current peak output current absolute maximum ratings v+ i q v in +15v -15v i out i pk 11.1c/w 9.5c/w -55c to +125c +300c -40c to +85c +150c jc jc t st t ld t c t j thermal resistance (regulator) thermal resistance (output switches) storage temperature range lead temperature range (10 seconds) case operating temperature msk4460 junction temperature 2 guaranteed by design but not tested. typical parameters are representative of actual device performance but are for reference only. v+=28v, t case =25c unless otherwise specified. maximum power dissipation must be limited according to voltage regulator power dissipation. measurements do not include offset current at 0v current command. continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle. 20ma load 20ma load 20ma load current command=0 volts @ 1 amp output 5ma load 5ma load 10 amps 10 amps @ 150c junction all switches off, v+=44v, 150c junction electrical specifications parameter units msk 4460 test conditions khz volts volts mv volts volts volts ma a/v ma v/a volts volts v/ sec mhz v/mv volts volts a volts nsec sec volts volts ma min. typ. max. 14 14.25 -15.75 - - 3.0 -13.5 - 1.8 -50 0.42 -12 -12 - - - - - - - - - - 3.0 - 16 - - - - - - - 2 0 0.5 - - 3 1.8 400 0.8 1.6 - - 86 2 - - - 19 15.75 -14.25 250 0.8 - +13.5 1.5 2.2 50 0.58 +12 +12 - - - - 1.92 750 1.6 - - 0.8 - 3.1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 3 notes: 4 1 2 3 4 5 1 1 1 pwm clock frequency regulators +15 vout -15 vout -15 vout ripple hall inputs vil vih analog section current command input range current command input current transconductance offset current current monitor current monitor voltage swing error amp e/a output swing slew rate unity gain bandwidth large signal voltage gain output section voltage drop across bridge (1 upper & 1 lower) voltage drop across bridge (1 upper & 1 lower) leakage current diode vsd trr dead time disable v il v in input current 4 5 rev. g 1/11
application notes msk 4460 pin descriptions v+ - is the power connection from the hybrid to the bus. the external wiring to the pin should be sized according to the rms current required by the motor. the pin should be by- passed by a high quality monolithic ceramic capacitor for high frequencies and enough bulk capacitance for keeping the v+ supply from drooping. 78 f of ceramic capacitance and 1700 f of bulk capacitance was used in the test circuit. the voltage range on the pin is from 16 volts up to 55 volts. motor drive a,b,c - are the connections to the motor phase windings from the bridge output. the wiring to these pins should be sized according to the required current by the motor. there are no short circuit provisions for these out- puts. shorts to v+ or v+ rtn from these pins must be avoided or the bridge will be destroyed. v+ rtn - is the power return connection from the module to the bus. all ground returns connect to this point from inter- nal to the module in a star fashion. all external ground con- nections to this point should also be made in a similar fash- ion. the v+ capacitors should be returned to this pin as close as possible. wire sizing to this pin connection should be made according to the required current. sig gnd - is a ground pin that connects to the ground plane for all low powered circuitry inside the hybrid. +15 v - is a regulated +15 volt output available for external uses. up to 20 ma is available at this pin. a 10 microfarad capacitor should be connected as close to this pin as pos- sible and returned to sig gnd along with a 0.22 microfarad monolithic ceramic capacitor. caution: see voltage regu- lator power dissipation. l1 - is a pin for connecting an external inductor to the dc - dc converter for generating -15 volts. a 47 h switching inductor capable of running at 250 khz and about 1 amp of dc current shall be used. connect the inductor between l1 and sig gnd. -15 v - is a regulated -15 volt output available for external uses. up to 20 ma is available at this pin. a 10 microfarad capacitor should be connected as close to this pin as pos- sible and returned to sig gnd along with a 0.22 microfarad monolithic ceramic capacitor. caution: see voltage regu- lator power dissipation 3 current monitor- is a pin providing a current viewing sig- nal for external monitoring purposes. this is scaled at 2 amps of motor current per volt output, up to a maximum of 5 volts, or 10 amps. as 10 amps is exceeded, the peaks of the waveform may become clipped as the rails of the amplifiers are reached. this voltage is typically 8 volts, equating to 16 amps of current peaks. e/a out - is the current loop error amp output connection. it is brought out for allowing various loop compensation cir- cuits to be connected between this and e/a-. e/a- - is the current loop error amp inverting input connec- tion. it is brought out for allowing various loop compensa- tion circuits to be connected between this and e/a out. hall a, b & c - are the hall input pins from the hall devices in the motor. these pins are internally pulled up to 15 volts. the halls reflect a 120/240 degree commutation scheme. disable - is a pin for externally disabling the output bridge. a ttl logic low will enable the bridge, and a ttl logic high will disable it. it is internally pulled low by a 5k ohm resistor. voltage regulator power dissipation - to figure volt- age regulator power dissipation and junction temperature, use the following as an example: given: v+ = 28v, msk 4460 +15v iq = 80ma, -15v iq = 40ma. external loads: +15v = 20 ma, -15v = 20 ma -15v converter efficiency = 50% p diss due to +15v iq,80 ma x 13v = 1.04 w p diss due to -15v iq, (40 ma / 0.5) x 13v = 1.04 w p diss due to +15v ext load, 20 ma x 13v = 260 mw p diss due to -15v ext load, (20 ma / 0.5) x 13v = 620mw p diss total = 1.04w + 1.04 w + 260 mw + 520mw = 2.86w 3.12w x 11.1c/w = 32c rise above case temperature maximum case temperature = 150c - 32c = 118c current command (+,-) - are differential inputs for con- trolling the module in current mode. scaled at 2 amps per volt of input command, the bipolar input allows both forward and reverse current control capability regardless of motor commutation direction. the maximum operational command voltage should be 5 volts for 10 amps of motor current. rev. g 1/11
1 = high level h = source note: because of the true 4 quadrant method of output switching, 0 = low level l = sink the output switches will pwm between the i command positive x = don't care - = open and i command negative states, with the average percentage based on i command being a positive voltage and a negative voltage. with a zero voltage i command , the output switches will modulate with exactly a 50% duty cycle between the i command positive and i command negative states. commutation truth table hall sensor phasing i command = pos. i command = neg. 120 hall a 1 1 0 0 0 1 1 0 x hall b 0 1 1 1 0 0 1 0 x hall c 0 0 0 1 1 1 1 0 x a? h - l l - h - - l b? - h h - l l - - l c? l l - h h - - - l a? l - h h - l - - l b? - l l - h h - - l c? h h - l l - - - l 4 application notes continued rev. g 1/11
bus voltage filter capacitors the size and placement of the capacitors for the dc bus has a direct bearing on the amount of noise filtered and also on the si ze and duration of the voltage spikes seen by the bridge. what is being created is a series rlc tuned circuit with a resonant frequency that is seen as a damped ringing every time one of the transistors switches. for the resistance, wire resistance, po wer supply impedance and capacitor esr all add up for the equivalent lumped resistance in the circuit. the inductance can be figur ed at about 30 nh per inch from the power supply. any voltage spikes are on top of the bus voltage and the back emf from the motor. all this must be taken into account when designing and laying out the system. if everything has been minimized, there is another solution. a second capacitance between 5 and 10 times the first capacitor and it should either have some esr or a resistor can be added in series with the second capacitor to help damp the voltage spikes. be careful of the ripple current in all the capacitors. excessive ripple current, beyond what the capacitors can handle, will destroy the capacitors. regulated voltage filter capacitors it is recommended that about 10 f of capacitance (tantalum electrolytic) for bypassing the + and -15v regulated outputs be placed as close to the module pins as practical. adding ceramic bypass capacitors of about 0.1 f to 1 f will aid in suppressing noise transients. general layout good pc layout techniques are a must. ground plane for the analog circuitry must be used and should be tied back to the sig gnd. ground plane for the power circuitry should be tied back to the v+ rtn pin, pin 16. pin 16 should be connected to pin 10 external to the hybrid by a single thick trace. this will connect the two ground planes together. low power startup when starting up a system utilizing the msk 4460 for the first time, there are a few things to keep in mind. first, because of the small size of the module, short circuiting the output phases either to ground or the dc bus will destroy the bridge. the curre nt limiting and control only works for current actually flowing through the bridge. the current sense resistor has to see the cur rent in order for the electronics to control it. if possible, for startup use a lower voltage and lower current power supply to tes t out connections and the low current stability. with a limited current supply, even if the controller locks up, the dissipation wil l be limited. by observing the e/a out pin which is the error amp output, much can be found out about the health and stability of t he system. an even waveform with some rounded triangle wave should be observed. as current goes up, the dc component of the waveform should move up or down. at full current (with a regular supply) the waveform should not exceed +8 volts positive peak, or -8 volts negative peak. some audible noise will be heard which will be the commutation frequency. if the motor squea ls, there is instability and power should be removed immediately unless power dissipation isn't excessive due to limited supply current. for compensation calculations, refer to the block diagram for all information to determine the amplifier gain for loo p gain calculations. 5 application notes continued rev. g 1/11
6 msk4460 test circuit rev. g 1/11
the information contained herein is believed to be accurate at the time of printing. msk reserves the right to make changes to its products or specifications without notice, however, and assumes no liability for the use of its products. please visit our website for the most recent revision of this datasheet. mechanical specifications m.s. kennedy corp. 4707 dey road liverpool, new york 13088 phone (315) 701-6751 fax (315) 701-6752 www.mskennedy.com 7 ordering information note: all dimensions are .010 inches unless otherwise labeled. esd triangle indicates pin 1. screening level part number MSK4460S msk4460d msk4460u msk4460g lead configuration industrial industrial industrial industrial straight down up gullwing mounting torque: 3-4 inch pounds weight= 31.5 grams typical caution: this is a non-hermetic device. do not expose plastic housing to liquid rev. g 1/11
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