FM3 CY9Ax4x-Series Low Power Arm® Cortex®-M3 Microcontroller (MCU) Family | Cypress Semiconductor

FM3 CY9Ax4x-Series Low Power Arm® Cortex®-M3 Microcontroller (MCU) Family

The Cypress FM3 family of 32-bit general-purpose MCUs is based on the Arm® Cortex®-M3 CPU. The FM3 CY9Ax4x-Series is a low power group that operates with a voltage range of 1.65V to 3.6V. The FM3 CY9Ax4x-Series is designed for low-power applications and delivers up to 40MHz of CPU speed, up to 256KB of flash, up to 32KB of work flash, separate power domains to reduce power consumption and support for USB 2.0, LCD control and HDMI-CEC.

CY9Ax4x-Series Highlights

Low Power MCU Subsystem

  • 40-MHz Arm® Cortex®​-M3 CPU with 1.65V to 3.6V operating voltage
  • Up to 256KB flash, 32KB SRAM with 32KB work flash
  • Separated power domains
  • 8ch DMA controller

Digital Subsystem

  • Up to 8x Base Timers
  • 1x Dual Timer, 1x Watch Counter
  • Up to 8x Multi-Function Serial (MFS) interfaces configurable as SPI, UART, I2C
  • 1x USB, up to 2x HDMI-CEC
  • External memory bus interface

Analog Subsystem

  • 2x 12-bit, 1-Msps ADCs with a 24-channel multiplexer input
  • LCD drive with support for up to 44 segments and 8 common outputs
  • 4MHz high-speed internal oscillator


  • 64/80/100-pin LQFP
  • 100-pin QFP
  • 64-pin QFN
  • 96/112-ball BGA

CY9Ax4x-Series Block Diagram

CY9Ax4x Series Block Diagram

Function Differences between each Low Power Line by part

Series CY9A150R CY9AB40N CY9AA40N CY9A340N CY9A140N
Flash/SRAM(KB) 512/64 256/32 256/32 256/32 256/32
GPIO 103 83 83 83 83
Base Timer 16 8 8 8 8
MFT 1 - - - -
QPRC 2 - - - 2
MFS 16 8 8 8 8
USB - 1 - 1 -
MFS 16 16 16 16 8
USB - 1 - 1 -

44SEG x 4COM or

40SEG x 8COM (Max)

44SEG x 4COM or

40SEG x 8COM (Max)

- -
FM3 CY9Ax4x-Series Datasheets
  • The FM3 CY9Ax4x-Series datasheets are intended to provide quick reference for this FM3 series.
FM3 CY9Ax4x-Series Flash Specifications
  • Flash Programming Manual explains the functions, operations and serial programming of the flash memory for FM3 CY9Ax4x-Series devices. This manual is intended for engineers engaged in the actual development of products using the FM3 devices.
FM3 CY9Ax4x-Series Technical Reference Manual
  • The FM3 Technical Reference Manual provides detailed information on the device features and how they work. It is intended for advance user's who want to understand what's going on under the hood.
Application Notes

Peripheral Driver Library

FM MCU Peripheral Driver Library (PDL)

The FM MCU Peripheral Driver Library (PDL) simplifies software development for the FM0+, FM3, and FM4 MCU families. The PDL reduces the need to understand register usage and bit structures, thus easing software development for the extensive set of peripherals in the FM families. You configure the library for the particular device, and then use API calls to initialize and use a peripheral. Using the PDL makes it easier to port code from one family to the other, because the same code supports all FM families.


Support Tools

Vendor Link Comments
IAR Systems!?architecture=ARM IAR Embedded Workbench for Arm 7.50.2 or later
Arm Keil Keil Embedded Development Tools for Arm 5.17 or later
GCC Arm Embedded GCC Arm Embedded 4.9-2015-q1-update or later
iSystem iSYSTEM winIDEA 9.12 or later



Click on the link below to download the tool

Product Description
Pin and Code Wizard Tool that helps set the IO ports for Cypress's 32-bit Arm Cortex FM MCUs
Serial Port Viewer Tool Tool that is used to monitor all available com ports and provides a terminal emulator
CMSIS-DAP USB Drivers CMSIS-DAP is the interface firmware for a Debug Unit that connects the Debug Port to USB. Debuggers, which execute on a host computer, connect via USB to the Debug Unit and to the Device that runs the application software
FLASH Programmer Tool that converts RS232C data to readable data on your PC
USB Wizard Tools that supports editing USB descriptors and templates

The Sample Programs ("Programs") are offered for use in developing systems for Cypress microcontrollers.

The Programs will be useful in the following situations:

  • I need a simple sample program, as I am going to develop software. The sequence of resource access, among others, can be confirmed using these Programs.
  • I would like to examine, before development, whether each resource will operate as expected.
    The Programs support several specifications, even for the operation of one resource.
  • If resources do not operate properly on my system, I would like software for which confirmation of operation has been completed. Cypress has confirmed the actual operation of the Programs on each of its microcontrollers, so you will be able to compare your program with the Program.

For the FM portfolios, code examples are provided with the Peripheral Driver Library (PDL). Download and install the PDL, and look in the examples folder.