AM9468 Green SINGLE PHASE FULL WAVE DIRECT PWM MOTOR DRIVER Description Pin Assignments The AM9468 is a high performance ultra low noise single phase (single-coil) brushless direct current (BLDC) fan and motor driver. The integrated full-bridge driver output stage uses a BTL linear driver (Top View) architecture to minimize audible switching noise and electromagnetic interference (EMI) providing a low noise solution. OUT1 1 OUT2 16 For system flexibility the motor speed can be controlled by either an external PWM signal or by a DC voltage or from a thermistor network. 2 V RF DD 15 Based on the input signal, the AM9468 adjusts the output duty cycle. REGH 3 GND 14 To help protect the motor coil, the AM9468 provides Rotor Lock 5VREG 4 Protection which shuts down the output drive if rotor lock is detected. PWM 13 The device automatically re-starts when the rotor lock is removed. In VCONT 5 CPWM 12 case of over voltage, the device shuts down the output drive and enters standby mode to help prevent over voltage stress on the coil. RMI 6 11 HIN- Over temperature shutdown provides thermal protection for the device. FG 7 10 HB A Tachometer output is provided by open-drain Frequency Generator RD 8 9 HIN+ (FG) Pin which allows external interface to monitor motor rotation or speed. The FG output is the magnetic change frequency. Additionally, a rotor lock detect output is provided by open-drain RD pin. TSSOP-16 The AM9468 is available in power capable low profile TSSOP-16 package. Applications Features 9V/ 12V / 15V BLDC Cooling Fans and Motors Single-Phase Full Wave BLDC Fan/Motor Drive with BTL Output CPU Cooling Fans for Notebooks and Desktop BLDC Fans (BTL Amplifier Gain = 49dB) Instruments Cooling Fans Low Noise Architecture Medium Voltage/ Low Power BLDC Motors Wide Operating Voltage Range: 2.4V to 18V PWM Speed Control with External PWM Input DC Voltage Speed Control by Adjusting VCONT and RMI Voltage Hall Bias Output: V = 1.25V HB Built-in Quick Start Circuit Lock Protection with Automatic Restart Frequency Generator (FG) Output Rotor Lock Detection (RD) Output Current Limit Circuit R Defines The Current Limit F R = 1 will Achieve 250mA Current Limit F Thermal Shut-Down (TSD) Circuit Lead-Free Finish RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3) Notes: 1. EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. All applicable RoHS exemptions applied. 2. See AM9468 Typical Applications Circuit (Notes 4 and 5 ) Motor Coil 1 OUT1 OUT2 16 SYSTEM V 2 RF DD 15 POWER D1 R F AM9468 C1 Dz 3 REGH GND 14 PWM signal for speed control 4 5VREG PWM 13 CPWM 5 VCONT CPWM 12 RMI 6 HIN- 11 R1 Hall 7 FG HB 10 8 HIN+ 9 RD Typical Applications Circuit for PWM Speed Control Motor Coil 1 OUT1 OUT2 16 SYSTEM V 2 RF POWER DD 15 D1 R F AM9468 C1 Dz 3 REGH GND 14 4 5VREG PWM 13 CPWM 5 VCONT CPWM 12 RMI 6 HIN- 11 VPWM R1 Hall 7 FG HB 10 8 RD HIN+ 9 Typical Applications Circuit for VCONT/RMI Control Notes: 4. C1 is for power stabilization and to strengthen the noise immunity and should be as close to the V pin as possible. The recommended value for C1 is DD 1F typically. The value of capacitor can be optimized depending on the operating mode, motor voltage and the motor current. For PWM speed control mode, with datasheet current capability, the recommended capacitor value is 1F. The value of the C1 should be checked in the motor design and route in its operating conditions if it is reduced or increased from the recommended value of 1F. 5. Diode D1 is for the reverse connection protection. In addition to power stabilization and noise immunity, C1 also absorbs regenerative motor spikes. Depending on the amount of regenerative voltage spike, value of C1 needs to be adjusted. The zener diode Dz is used to clamp the regenerative voltage spike from the motor operation to safe level when reverse blocking diode D1 is used. If reverse blocking diodes is not used, the use of zener clamp Dz depends on the supply voltage capability to effectively sink the regenerative energy and voltage spike. The value of C1 and the requirement Dz needs to be verified on each application design. 2 of 16 AM9468 May 2016 Diodes Incorporated www.diodes.com Document number: DS38663 Rev. 1 - 2 NEW PRODUCT