A3906 Low Voltage Stepper and Single/Dual DC Motor Driver Features and Benefits Description 2.5 to 9 V operation Designed for pulse width modulated (PWM) control of low Internal PWM current limit control voltage stepper motors, and single and dual DC motors, the Synchronous rectification for reduced power dissipation A3906 is capable of output currents up to 1 A per channel and Peak current output flag operating voltages from 2.5 to 9 V. Undervoltage lockout The A3906 has an internal fixed off-time PWM timer that Low R outputs DS(on) sets a peak current based on the selection of a current sense Small package resistor. An overcurrent output flag is provided that notifies Brake mode for DC motors the user when the current in the motor winding reaches the Sleep function peak current determined by the sense resistor. The fault output Crossover-current protection does not affect driver operation. Thermal shutdown The A3906 is provided in a 20-contact, 4 mm 4 mm, 0.75 mm nominal overall height QFN, with exposed pad for enhanced thermal dissipation. It is lead (Pb) free, with 100% matte tin leadframe plating. Package: 20-contact QFN (suffix ES) Applications include the following: Digital still cameras (DSC) Cell phone cameras USB powered devices Battery powered devices Approximate size Typical Applications 0.1 F 0.1 F 0.1 F 0.1 F CP1 CP2 CP3 CP4 CP1 CP2 CP3 CP4 VCP VCP 0.1 F 0.1 F SLEEP VBB SLEEP VBB A3906 10 F A3906 10 F 10 V IN1 10 V IN1 IN2 OUT1A IN2 OUT1A M IN3 IN3 OUT1B OUT1B +5 V IN4 SENSE1 +5 V IN4 SENSE1 M OUT2A OUT2A M FL1 FL1 OUT2B OUT2B FL2 FL2 SENSE2 SENSE2 GND GND Dual DC motor application Stepper motor application 3906-DS, Rev. 4Low Voltage Stepper and Single/Dual DC Motor Driver A3906 Selection Guide Part Number Packing Package A3906SESTR-T 1500 pieces per 7-in. reel 20-pin QFN with exposed thermal pad Absolute Maximum Ratings Characteristic Symbol Notes Rating Units Load Supply Voltage V 9.6 V BB Logic Input Voltage Range V 0.3 to 7 V IN Continuous 0.5 V Sense Voltage V SENSEx Pulsed, t < 1 s1V w Continuous 1 A May be limited by duty cycle, ambient Output Current I OUT temperature, and heat sinking. Under Peak, DC < 30% 1.5 A any set of conditions, do not exceed Continuous 2 A Output Current in Paralleled the specified current rating or a junction I OUT(par) Operation temperature of 150C. Peak, DC < 30% 2.5 A Operating Temperature Range T Range S 20 to 85 C A Junction Temperature T 150 C J(max) Storage Temperature Range T 40 to 150 C stg Thermal Characteristics may require derating at maximum conditions, see application information Characteristic Symbol Test Conditions* Value Units R Package Thermal Resistance 4-layer PCB based on JEDEC standard 37 C/W JA *Additional thermal information available on the Allegro website. Terminal List Table Number Name Function 1 CP2 Charge pump capacitor terminal 2 2 GND Ground Pin-out Diagram 3 SLEEP Sleep logic input, active low 4 IN1 Control input 5 IN2 Control input 6 IN3 Control input 7 IN4 Control input CP2 1 SENSE1 15 8 FL1 Current limit flag, bridge 1 GND OUT1B 2 14 9 FL2 Current limit flag bridge 2 SLEEP 3 13 VBB PAD 10 OUT2A DMOS full-bridge 2, output A IN1 4 12 OUT2B 11 SENSE2 Current sense resistor terminal, bridge 2 IN2 5 SENSE2 11 12 OUT2B DMOS full-bridge 2, output B 13 VBB Supply Voltage 14 OUT1B DMOS full-bridge 1, output B 15 SENSE1 Current sense resistor terminal, bridge 1 16 OUT1A DMOS full-bridge 1, output A 17 VCP Reservoir capacitor terminal 18 CP3 Charge pump capacitor terminal 3 19 CP1 Charge pump capacitor terminal 1 20 CP4 Charge pump capacitor terminal 4 PAD Exposed pad for enhanced thermal performance Allegro MicroSystems, LLC 2 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000 www.allegromicro.com 6 20 IN3 CP4 7 19 IN4 CP1 FL1 8 18 CP3 FL2 9 17 VCP 10 16 OUT2A OUT1A