A3992SB-T

A3992 DMOS Dual Full-Bridge Microstepping PWM Motor Driver Features and Benefits Description ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ Designed for pulse width modulated (PWM) current control of bipolar microstepped stepper motors, the A3992 is capable of continuous output currents to ±1.5 A and operating voltages to 50 V. Internal fixed off-time PWM current control timing circuitry can be programmed via the serial interface to operate in slow, fast, or mixed decay modes. ±1.5 A, 50 V continuous output rating Low RDS(on) DMOS output drivers Short-to-ground protection Shorted load protection Optimized microstepping via six bit linear DACs Programmable mixed, fast, and slow current decay modes 4 MHz internal oscillator for digital timing Serial interface controls chip functions Synchronous rectification for low power dissipation Internal UVLO and thermal shutdown circuitry Crossover-current protection Inputs compatible with 5 or 3.3 V control signals Sleep and Idle modes The desired load current level is set via the serial port with two six bit linear DACs in conjunction with a reference voltage. The six bits of control allow maximum flexibility in torque control for a variety of step methods, from microstepping to full step drive. Load current is set in 1.56% increments of the maximum value. Synchronous rectification circuitry allows the load current to flow through the low RDS(on) of the DMOS output driver during current decay. This feature eliminates the need for external clamp diodes in most applications, saving cost and external component count, while minimizing power dissipation. Packages 24 pin batwing DIP (suffix B) and 24 pin TSSOP with exposed thermal pad (suffix LP) Internal circuit protection includes short-to-ground, shorted load, thermal shutdown with hysteresis, and crossover current protection. Special power up sequencing is not required. The A3992 is supplied in a thin profile (1.2 mm maximum height) 24 pin TSSOP (suffix LP) with exposed thermal pad and a 24 pin plastic DIP with dual copper batwing tabs (suffix B). The exposed thermal pad on the LP is at ground potential and needs no electrical isolation. Both packages are lead (Pb) free with 100% matte tin leadframe plating. LP package approximate scale Typical Application 0.22 μF VREG 0.22 μF CP1 0.22 μF VCP VDD 10 μF CP2 5 kΩ Microcontroller or Controller Logic ROSC CLOCK DATA VBB1 A3992 VBB2 100 μF OUT1A OUT1B SENSE1 0.1 μF STROBE REF SLEEP OUT2A OUT2B SENSE2 0.1 μF 3992DS, Rev. 2 DMOS Dual Full-Bridge Microstepping PWM Motor Driver A3992 Selection Guide Part Number A3992SB-T 15 pieces/tube Packing Package A3992SLPTR-T Tape, 4000 pieces/reel 24 pin batwing DIP 24 pin TSSOP with exposed thermal pad Absolute Maximum Ratings Characteristic Load Supply Voltage Symbol Notes Rating Units 50 V ±1.5 A V VBB Output current rating may be limited by duty cycle, ambient temperature, and heat sinking. Under any set of conditions, do not exceed the specified current rating or a junction temperature of 150°C. Output Current IOUT Logic Supply Voltage VDD 7.0 Logic Input Voltage Range VIN –0.3 to 7 V 50 V 50 V 3 V 500 mV –20 to 85 ºC VBBx to OUTx Voltage OUTx to SENSEx Voltage REF Reference Voltage SENSE Voltage (DC) VREF VSENSE Operating Ambient Temperature TA Maximum Junction Temperature TJ(max) 150 ºC Tstg –55 to 150 ºC Storage Temperature Range S Thermal Characteristics* Characteristic Package Thermal Resistance Symbol RθJA Notes Rating Units B package on 4-layer PCB 26 °C/W B package on 2-layer PCB with 3.15 in.2 2 oz. copper each side 36 °C/W LP package on 4-layer PCB 28 °C/W LP package on 2-layer PCB with 3.8 in.2 2 oz. copper each side 32 °C/W *Additional thermal data available on the Allegro website. Allegro MicroSystems, LLC 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 2 DMOS Dual Full-Bridge Microstepping PWM Motor Driver A3992 Functional Block Diagram 0.22 µF 0.22 µF CP1 CP2 VREG 2V VDD UVLO and Fault Detect Charge Pump Regulator Bandgap VCP MUX 0.22 µF To VDD VCP 6 Bit Linear DAC DMOS Full Bridge 1 VBB1 >47 µF Internal Oscillator OSC OUT1A Programmable PWM Timer OSC Select/ Divider OUT1B Fixed-Off Blank Mixed Decay SENSE1 Gate Drive CLOCK To VDD OCP Control Logic DATA Serial Port STROBE Phase 1,2 Sync Rect Mode Sync Rect Disable Mode 1, 2 DMOS Full Bridge 2 VBB2 OUT2A SLEEP OUT2B Programmable PWM Timer To 2V VREF REF Fixed-Off Blank Mixed Decay Buffer SENSE2 0.1 µF 6 Bit Linear DAC Allegro MicroSystems, LLC 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 3 A3992 DMOS Dual Full-Bridge Microstepping PWM Motor Driver ELECTRICAL CHARACTERISTICS1 valid at TA= 25°C, VBB = 50 V, fPWM < 50 kHz, unless otherwise noted Characteristic Symbol Test Conditions Min. Typ.2 Max. Units Output Drivers Operating, IOUT = ±1.5 A 15 – 50 V Load Supply Voltage Range VBB During Sleep mode 0 – 50 V VOUT = VBB –