AM9468

Description

The AM9468 is a high performance ultra low noise single phase (single –coil) brushless direct current (BLDC) fans and motors. The integrated full-bridge driver output stage uses a BTL linear driver architecture to minimize audible switching noise and electromagnetic interference (EMI) providing a low noise solution.

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. Based on the input signal, the AM9468 adjusts the output duty cycle.

To help protect the motor coil, the AM9468 provides Rotor Lock Protection which shuts down the output drive if rotor lock is detected. The device automatically re-starts when the rotor lock is removed. In case of over voltage, the device shuts down the output drive and enters standby mode to help prevent over voltage stress on the coil. Over temperature shutdown provides thermal protection for the device.

A Tachometer output is provided by open-drain Frequency Generator (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

The AM9468 is available in power capable low profile TSSOP16 package.

Feature(s)

• Single-Phase Full Wave BLDC Fan/Motor Drive with BTL Output (BTL Amplifier Gain=49dB)
• Low Noise Architecture
• 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_HB=1.25V
• Built-In Quick Start Circuit
• Lock Protection with Automatic Restart
• Frequency Generator (FG) Output
• Rotor Lock Detection (RD) Output
• Current Limit Circuit
• R_F defines the current limit; R_F=1 will give 250mA Current limit
• Thermal Shut-down (TSD) Circuit
• Low Profile Package: TSSOP16 with Exposed Pads for Power Handling Capability
• Totally Lead-Free & Fully RoHS Compliant
• Halogen and Antimony Free. “Green” Device

Application(s)

• 9V/12V/15V BLDC Cooling Fans and Motor
• CPU Cooling Fans for Notebooks and Desktop BLDC Fans
• Instruments Cooling Fans
• Medium Voltage, Low Power BLDC Motors