A3967SLBTR-T

A3967 Microstepping Driver with Translator Features and Benefits Description ▪ ±750 mA, 30 V output rating ▪ Satlington® sink drivers ▪ Automatic current-decay mode detection/selection ▪ 3.0 to 5.5 V logic supply voltage range ▪ Mixed, fast, and slow current-decay modes ▪ Internal UVLO and thermal shutdown circuitry ▪ Crossover-current protection The A3967 is a complete microstepping motor driver with builtin translator. It is designed to operate bipolar stepper motors in full-, half-, quarter-, and eighth-step modes, with output drive capability of 30 V and ±750 mA. The A3967 includes a fixed off-time current regulator that has the ability to operate in slow, fast, or mixed current-decay modes. This current-decay control scheme results in reduced audible motor noise, increased step accuracy, and reduced power dissipation. The translator is the key to the easy implementation of the A3967. By simply inputting one pulse on the STEP input the motor will take one step (full, half, quarter, or eighth depending on two logic inputs). There are no phase-sequence tables, highfrequency control lines, or complex interfaces to program. The A3967 interface is an ideal fit for applications where a complex μP is unavailable or over-burdened. Package: 24-pin SOIC with internally fused pins (suffix LB) Internal circuit protection includes thermal shutdown with hysteresis, under-voltage lockout (UVLO) and crossovercurrent protection. Special power-up sequencing is not required. The A3967 is supplied in a 24-pin SOIC, which is lead (Pb) free with 100% matte tin leadframe plating. Four pins are fused internally for enhanced thermal dissipation. The pins are at ground potential and need no insulation. Not to scale Functional Block Diagram LOGIC SUPPLY VCC LOAD SUPPLY UVLO AND FAULT DETECT 14 REF. SUPPLY REF VBB1 20 1 ÷8 DAC SENSE + - RC1 OUT1A PWM LATCH BLANKING MIXED DECAY 23 16 OUT1B 21 PWM TIMER 3 STEP 10 MS2 13 SLEEP 17 CONTROL LOGIC MS1 12 SENSE1 TRANSLATOR DIR 11 RESET 22 3 5 ENABLE 15 VPF OUT2A 24 PFD VBB2 9 PWM TIMER 3 OUT2B 4 PWM LATCH BLANKING MIXED DECAY 2 RC2 + - DAC 8 6 26184.24H 7 18 19 SENSE2 Dwg. FP-050-3A A3967 Microstepping Driver with Translator Selection Guide Part Number A3967SLBTR-T Packing Package 24-pin SOIC with internally fused pins 1000 per reel Absolute Maximum Ratings Characteristic Symbol Notes Rating Units Load Supply Voltage VBB 30 V Logic Supply Voltage VCC 7.0 V Logic Input Voltage Range VIN tw > 30 ns –0.3 to 7.0 V tw < 30 ns –1 to 7.0 V VSENSE 0.68 V Reference Voltage Sense Voltage VREF VCC mA Continuous ±750 mA Output Current IOUT Peak ±850 mA – – –20 to 85 ºC 150 ºC –55 to 150 ºC Value Units 50 ºC/W 35 ºC/W 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. Package Power Dissipation PD See graph Operating Ambient Temperature TA Range S Maximum Junction Temperature Fault conditions that produce excessive junction temperature will activate the device’s thermal shutdown circuitry. These conditions can be tolerated but should be avoided. TJ(max) Storage Temperature Tstg Thermal Characteristics Characteristic Symbol Package Thermal Resistance, Junction to Ambient RθJA Test Conditions* 2-layer PCB, 1.3 in.2 2-oz. exposed copper 4-layer PCB, based on JEDEC standard ALLOWABLE PACKAGE POWER DISSIPATION (W) *Additional thermal information available on Allegro website. 5 RQJT = 6.0oC/W 4 3 R QJA = 35°C/W 2 R QJA = 50°C/W 1 0 25 50 75 100 TEMPERATURE IN oC 125 150 Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 A3967 Microstepping Driver with Translator ELECTRICAL CHARACTERISTICS at TA = +25°C, VBB = 30 V, VCC = 3.0 V to 5.5V (unless otherwise noted) Limits Characteristic Symbol Test Conditions Min. Typ. Max. Units 4.75 – 30 V During sleep mode 0 – 30 V VOUT = VBB –