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Details, datasheet, quote on part number:8904
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Datasheet text preview:
PRELIMINARY INFORMATION
(subject to change without notice) January 24, 2003
8904
3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER WITH BACK-EMF SENSING
The A8904SLB and A8904SLP are three-phase brushless dc motor controller/drivers designed for applications where accurate control of high-speed motors is required. The three half-bridge outputs are low on-resistance n-channel DMOS devices capable of driving up to 1.25 A. The A8904 provides complete, reliable, self-contained back-EMF sensing, motor startup and running algorithms. A programmable digital frequency-locked loop speed control circuit together with the linear current control circuitry provides precise motor speed regulation. A serial port allows the user to program various features and modes of operation, such as the speed control parameters, startup current limit, sleep mode, direction, and diagnostic modes. The A8904 is fabricated in Allegro's BCD (Bipolar CMOS DMOS) process, an advanced mixed-signal technology that combines bipolar, analog and digital CMOS, and DMOS power devices. The A8904SLB is provided in a 24-lead wide-body SOIC batwing package. The A8904SLP is provided in a thin (<1.2 mm), 28-lead SSOP package with an exposed thermal pad.
Data Sheet 26301.5
A8904SLB (SOIC)
Features
Absolute Maximum Ratings
at TA = +25°C
Load Supply Voltage, VBB . . . . . . . . . . 15 V Output Current, IOUT . . . . . . . . . . . . ±1.4 A* Logic Supply Voltage, VDD . . . . . . . . . 7.0 V Logic Input Voltage Range, VIN (continuous) . . . . -0.3 V to VDD + 0.3 V (tw <30 ns) . . . . . -1.0 V to VDD + 1.0 V Package Power Dissipation, PD See Graph Operating Temperature Range, TA . . . . . . . . . . . . . . . . -20°C to +85°C Junction Temperature, TJ . . . . . . . +150°C Storage Temperature Range, TS . . . . . . . . . . . . . . . -55°C to +150°C
* Output current rating may be restricted to a value determined by system concerns and factors. These include: system duty cycle and timing, ambient temperature, and use of any heatsinking and/or forced cooling. For reliable operation, the specified maximum junction temperature should not be exceeded. Fault conditions that produce excessive junction temperature will activate device thermal shutdown circuitry. These conditions can be tolerated, but should be avoided.
Pin-for-pin replacement for A8902CLBA Startup commutation circuitry Sensorless commutation circuitry Option of external sector data tachometer signal Option of external speed control Oscillator operation up to 20 MHz Programmable overcurrent limit Transconductance gain options: 500 mA/V or 250 mA/V Programmable watchdog timer Directional control Serial Port Interface TTL-compatible inputs System diagnostics data out ported in real time Dynamic braking through serial port or external terminal Always order by complete part number, e.g., A8904SLB .
8904 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER
Functional Block Diagram
(A8904SLB terminal numbers shown)
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115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 2003 Allegro MicroSystems, Inc.
8904 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER
LB (SOIC) Package
LP (HTSSOP) Package
A8904SLP (HTSSOP)
* Measured on "High-K" multi-layer PWB per JEDEC Standard JESD51-7. Measured on typical two-sided PWB with power tabs (LB package) or thermal pad (LP package) connected to copper foil with an area of three square inches (1935 mm2). See Application Note 29501.5, Improving Batwing Power Dissipation, for additional information.
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8904 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER
ELECTRICAL CHARACTERISTICS at TA = +25°C, VDD = 5.0 V
Limits Characteristic Logic Supply Voltage Logic Supply Current Undervoltage Threshold Load Supply Voltage Load Supply Current Thermal Shutdown Thermal Shutdown Hysteresis Output Drivers Output Leakage Current Total Output ON Resistance (source + sink + RS) Output Sustaining Voltage Clamp Diode Forward Voltage Control Logic Logic Input Voltage Logic Input Current BRAKE Threshold BRAKE Hysteresis Current BRAKE Current DATA Output Voltage CST Current CST Threshold Filter Current Symbol VDD I DD UVLO VBB IBB TJ T J I DSX rDS(on) VD S ( s u s ) VF VI N ( 0 ) VIN(1) I IN(0) I IN(1) V BRK IBRKL I BRK VO U T ( 0 ) VOUT(1) IC S T VC S T H VCSTL IFILTER VBB = 14 V, VOUT = 14 V, sleep mode VBB = 14 V, VOUT = 0 V IOUT = 600 mA VBB = 14 V, IOUT = IOUT(MAX), L = 3 mH IF = 1.0 A SECTOR DATA, RESET, CLK, CHIP SELECT, OSC VIN = 0 V VIN = 5.0 V VBRK = 750 mV Brake set, D2 = 1, IBRK = 750 mV IOUT = 500 µA IOUT = -500 µA Charging Discharging, VCST = 2.5 V High Low Charging Discharging Leakage, VFILTER = 2.5 V Filter Threshold CD Current (CD1 or CD2) CD Current Matching CD Threshold CD Input Leakage VF I L T E R T H ICD -- VC D T H ICDIL Charging Discharging ICD(DISCHRG)/ICD(CHRG) Test Conditions Operating Operating Sleep mode Decreasing VDD Increasing VDD Operating Operating Sleep mode Min. 4.5 -- -- -- -- 4.0 -- -- -- -- -- -- -- 14 -- -- 2.0 -- -- 1.5 -- -- -- 3.5 -9.0 -- 2.25 0.85 -9.0 9.0 -- 1.57 -18 32 1.8 2.25 -- Typ. 5.0 7.5 250 3.6 3.9 -- 4.0 20 165 20 200 -2.0 1.0 -- 1.25 -- -- -- -- 1.75 4.0 20 -- -- -10 500 2.5 1.0 -10 10 -- 1.85 -20 40 2.0 2.5 -- Max. 5.5 10 500 -- -- 14 8.0 30 -- -- 300 -15 1.4 -- 1.5 0.8 -- -0.5 ±1.0 2.0 -- -- 1.5 -- -11 -- 2.75 1.15 -11 11 ±5.0 2.13 -22 48 2.2 2.75 1.0 Units V mA µA V V V mA µA °C °C µA µA V V V V µA µA V µA µA V V µA µA V V µA µA nA V µA µA -- V µA
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115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000
8904 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER
ELECTRICAL CHARACTERISTICS continued
Limits Characteristic CWD Current Symbol I CWD Test Conditions Charging, D26 = 0, D27 = 0 Charging, D26 = 0, D27 =1 Charging, D26 = 1 D27 = 0 Charging, D26 = 1, D27 =1 CWD Threshold Voltage Max. FLL Oscillator Frequency Oscillator High Duration Oscillator Low Duration Maximum Output Current VT L VTH fOSC ton toff IOUT(MAX) D3 = 0, D4 = 0, D28 = 0 D3 = 0, D4 = 1, D28 = 0 D3 = 1, D4 = 0, D28 = 0 D3 = 1, D4 = 1, D28 = 0 D3 = 0, D4 = 0, D28 = 1 D3 = 0, D4 = 1, D28 = 1 D3 = 1, D4 = 0, D28 = 1 D3 = 1, D4 = 1, D28 = 1 Transconductance Gain Centertap Resistors Back-EMF Threshold with respect to VCTAP at FCOM transition gm RCT -- D28 = 1 D28 = 0 Min. -9.0 -18 -27 -36 0.22 2.25 20* 20 20 1.0 0.9 500 -- 500 415 -- -- 210 420 5.0 5.0 -5.0 Typ. -10 -20 -30 -40 0.25 2.5 -- -- -- 1.2 1.0 600 250 600 500 300 125 250 500 10 20 -20 Max. -11 -22 -33 -44 0.28 2.75 -- -- -- 1.4 1.1 700 -- 700 585 -- -- 290 580 13 37 -37 Units µA µA µA µA V V MHz ns ns A A mA mA mA mA mA mA mA/V mA/V k mV mV
Negative current is defined as coming out of (sourcing) the specified device terminal. * Operation at an oscillator frequency greater than the specified minimum value is possible but not waranteed.
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