AM9469
Green
LOW NOISE SINGLE PHASE FULL WAVE
DIRECT PWM MOTOR DRIVER
Description Pin Assignments
The AM9469 is a high performance, ultra-low noise single phase
(single-coil) brushless direct current (BLDC) fan and motor driver. The
(Top View)
integrated full-bridge driver output stage uses BTL linear driver
architecture to minimize audible switching noise and Electromagnetic
Interference (EMI) providing a low noise solution.
OUT1
1
16 OUT2
For system flexibility the motor speed can be controlled by either an
V 2
DD RF
15
external PWM signal or by a DC voltage or from a thermistor network.
Based on the input signal, the AM9469 adjusts the output duty cycle. REGH
3 14 GND
5VREG
4 PWM
13
To help protect the motor coil, the AM9469 provides Rotor Lock
Protection which shuts down the output drive if rotor lock is detected.
VCONT 5 CPWM
12
The device automatically restarts when the rotor lock is removed. In
case of over voltage, the device shuts down the output drive and
RMI 6 IN2
11
enters standby mode to help prevent over voltage stress on the coil.
FG
7 10 HB
Over temperature shutdown provides thermal protection for the
device.
RD
8 9 IN1
A Tachometer output is provided by the open-drain Frequency
Generator (FG) Pin which allows external interface to monitor motor
TSSOP-16EP (Type DX)
rotation or speed. The FG output is the magnetic change frequency.
Additionally, a rotor lock detect output is provided by the open-drain
RD Pin.
AM9469 is available in thermally enhanced TSSOP-16EP (Type DX)
with exposed pad.
Features Applications
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: VHB = 1.25V
Built-In Quick Start Circuit
Lock Protection with Automatic Restart
Frequency Generator (FG) Output
Rotor Lock Detection (RD) Output
Current Limit Circuit
RF Defines The Current Limit; RF = 1 will Achieve 250mA
Current Limit
Thermal Shut-Down (TSD) Circuit
Low Profile Package: TSSOP-16EP (Type DX) with Exposed
Pads for Power Handling Capability
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) & 2015/863/EU (RoHS 3) compliant. All applicable RoHS exemptions applied.
2. See
AM9469
Typical Applications Circuit (Notes 4 & 5)
Motor Coil
1 OUT1
OUT2 16
SYSTEM
V
2 RF
DD 15
POWER
D1
R
F
AM9469
C1
Dz
3 REGH
GND 14
PWM signal for
speed control
4 5VREG PWM
13
CPWM
5 VCONT CPWM 12
RMI
6 IN2 11
R1
Hall
7 FG HB 10
8 IN1 9
RD
Typical Applications Circuit for PWM Speed Control
Motor Coil
1 OUT1
OUT2 16
SYSTEM
2 V
RF
POWER DD 15
D1
R
F
AM9469
C1
Dz
3 REGH
GND 14
4 5VREG
PWM
13
CPWM
CPWM
5 VCONT 12
RMI
6 IN2 11
VPWM
R1
Hall
7 FG HB 10
8 RD IN1 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 form 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
AM9469 April 2018
Diodes Incorporated
www.diodes.com
Document number: DS38810 Rev. 2 - 2