AH5773
SINGLE PHASE MOTOR DRIVER WITH
INTERNAL HALL EFFECT LATCH SENSOR
Description
The AH5773 is a high performance, single chip solution for driving
single-coil brushless direct current (BLDC) fans and motors. The
integrated full-bridge driver output stage uses soft switching to
minimize audible switching noise and electromagnetic interference
(EMI) providing a low noise solution.
To simplify circuit design and minimize external components, the
device integrates a stable high sensitivity Hall-effect sensor, voltage
and temperature compensated internal references, amplifiers and the
output H-bridge power switches with low RDSON. For system flexibility,
the motor speed can be controlled by changing the duty ratio of the
PWM signal at the PWM pin or adjusting the supply voltage.
To help protect the motor coil, the AH5773 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. The device enters standby mode when PWM pin is pulled low
for longer than 65ms. In standby mode, AH5773 consumes less than
100µA.
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.
The AH5773 is available in space saving small low profile U-
DFN2020-6 and MSOP-8EP packages.
Pin Assignments
FG 1
PWM 2
O2 3
GND 4
(Top View)
Pad
8 NC
7 NC
6 VDD
5 O1
MSOP-8EP
(Top View)
PWM 1
6 FG
VDD 2
O2 3
5 O1
Pad 4 GND
U-DFN2020-6
Features
• Supports Single-Phase Full Wave BLDC Fan/Motor Drive
• Wide Operating Voltage Range: 2.4V to 18V
• Built-in High Sensitivity Hall Effect Sensor
• Built-in H-Bridge with Low RDSON Resistance
• PWM Input for Speed Control
• Standby Feature with IDD <100µA
• Soft Switching for Low Noise DC Fan Motor Applications
• Rotor Lock Protection with Automatic Re-Start
• tOFF Clear When PWM Is Low for Greater Than 65ms
• Over Voltage Shutdown
• Thermal Protection
• Tachometer (FG) Output
• Small Low-Profile Package: U-DFN2020-6 and MSOP-8EP with
Exposed Pads for Power Handling Capability
• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
• Halogen and Antimony Free. “Green” Device (Note 3)
Applications
• 5V/ 9V/ 12V/ 15V Min. BLDC Cooling Fans and Motors
• Netbook/ Notebook and Desktop BLDC Fans
• Instruments Cooling Fans
• Medium Voltage/ Low Power BLDC Motors
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AH5773
Document number: DS35444 Rev. 2 - 2
1 of 17
www.diodes.com
January 2015
© Diodes Incorporated