FAH4840-269128 Datasheet, PDF (17/21 Pages) List of Unclassifed Manufacturers – FAH4840 Haptic Driver for Linear Resonant Actuators (LRAs)

Host
GPIO
V_DD
PWM
SCL
SDA
FAH4840
EN GND
MDN
Actuator
MDP
Figure 12. LRA System Block Diagram
Table 24.
LRA Resonant Actuator Function
PWM Duty Cycle⁽⁴⁾
VDD
90/10%
PWM
Duty
Cycle
GND
LRA Drive Voltage at Resonant Frequency
VDD
MDP
MDN
GND
VDD
50/50%
PWM
Duty
Cycle
GND
VDD
MDP
MDN
GND
VDD
VDD
MDN
10/90%
PWM
Duty
Cycle
GND
MDP
GND
Note:
4. PWM frequency is a multiple of the LRA resonant frequency. This is controlled by I²C registers CTRL_DIV1 and
CTRL_DIV2. For example, if the LRA resonant frequency is 175 Hz, the PWM frequency would be 14.5 kHz and
the I²C CTRL_DIV1 and CTRL_DIV2 registers would be programmed to 1/83.
© 2013 Fairchild Semiconductor Corporation
FAH4840 • Rev. 1.0.0
17
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