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• Ultrasonic Park Assist Flash MCU ( ❋ Items in this solution Δ Other related products )
  Part Number Input
HT45F391 - 4.5V ~ 5.5V 11 / 8bitx8 2 4KW/160 HIRC/LIRC BCU OPA/SCF/AEP 16NSOP
Δ HT45F39 8V ~ 16V - 11 / 8bitx8 2 4KW/160   BCU OPA/SCF/AEP 16NSOP
• RAM Mapping LED Controller & Driver ( ❋ Items in this solution Δ Other related products )
  Part Number VDD Max. Resolution
Row x Com
Row Source
Current (Min.)
Com Sink
Current (Min.)
Interface Keyscan PACKAGE
HT16K33 4.5V ~ 5.5V 16 x 8
12 x 8
8 x 8
20mA 160mA I²C 13 x 3
10 x 3
8 x 3
Δ HT1632C 4.5V ~ 5.5V 32 x 8
24 x 16
50mA 250mA 4-Wire - 48LQFP
Δ HT1635A 4.5V ~ 5.5V 44 x 8 50mA 250mA 4-Wire - 64LQFP
Δ HT1635B 4.5V ~ 5.5V 44 x 8 50mA 250mA I²C - 64LQFP

Ultrasonic distance measurement products can provide improved measurements over the traditional tape measurement type in applications such as building, decoration, engineering and so on.

The Holtek HT45F391 MCU is specifically designed for such handheld ultrasonic distance measurement applications. The ultrasonic echo signal will be amplified, filtered and digitally processed in the internal dedicated ultrasonic sensor circuits. Holtek also provides users with all required technical support related to the product development, including block diagram, application circuits, PCBs and component list etc. The associated technical documents can be obtained by clicking on the “Learn more about our application solutions”.


Application Areas

Ultrasonic distance measurement products, handheld ultrasonic rangefinders and ultrasonic sensor applications.


Simple products and various applications

suitable for building, decoration and sensor applications;Operation voltage: 4.5V~5.5V Measurement range: 500mm ~ 3000mm with an accuracy of 0.3cm, also uses an external NTC to measure environment temperature to adjust the sound velocity.


Fewer components, smaller size and simplified production

16-NSOP package and internal 5V Shunt Regulator without need for external LDO.


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System Architecture and Connection Diagram

This application solution provides a reference design which is a highly integrated solution using very few external components. It includes a power supply circuit, temperature detection circuit reference voltage circuit, digital LED driver circuit and ultrasonic transmitter and receiver circuit etc. The application shows a complete ultrasonic distance measurement reference design solution.

(C90003-A.ZIP) Ultrasonic Distance Measurement host
Description Files   Solution Description and Application Notes
Application Circuits Protel format
PCB Protel format
Block Diagram PDF
Code Source code
Component List   Excel format
(C90003-B.ZIP) Separate Transmitter/Receiver Ultrasonic Probe
Description Files   Solution Description and Application Notes
Application Circuits Protel format
PCB Protel format
Block Diagram   PDF
Code   Source code
Component List   Excel format


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