I hope you have gone through my previous blogs on NXP MCX Microcontroller and MCXA Microcontroller Series.
Now that you have a good overview of the MCXA Microcontroller, we can start getting into further details.
To start with we can discuss various hardware related things which are worth understanding.
Before you start working on a project using MCXA microcontroller, my recommendation is that, you go through the MCXA microcontroller datasheet, it will help you understand what all you get in the MCU.
MCXA Microcontroller is based on ARM Cortex-M33 Core, MCXA Series has two MCU range MCXA14X and MCXA14X, the main difference between the two is the clock frequency, 15x series operates up to 96Mhz and 14x Series works up to 48Mhz.
There are three packages available LQFP64, QFN48, QFN32.
Please note the following:
(all pins mentioned below can be configured for any other function after power up in the code)
Functionality not available
- There is No FPU, no DSP extension instruction set, no TrustZone, no MPU. Carefully select the MCU considering the requirement.
- DAC is mentioned in the Analog compare section, please don’t get confused, there is no DAC in the MCU.
Operating Voltage and 5V Tolerant IOs
- MCU Operating Voltage range is 1.71V to 3.6V DC, only a few selected pins are 5V tolerant, please check carefully the datasheet. The pins which are 5V tolerant are marked with 5VTOL tag. See the image below.
Operating Temperature
- Operating Temperature range is -40 to 125 Degree C
External Crystal
- P1_30 & P1_31 are disabled by default But, can be configured to be used for external crystal. At power up MCU will start with internal oscillator clock and then if the code is configured for an external oscillator. The Crystal connected on these two pins will start.
PIN MUX
Each Pin of the MCU has multiple function and any function can be selected. Pin Mux information is available in the datasheet (see the attachment inside PDF).
Pin Mux Xls sheet will show you default functionality of each pin in the table. Pin details are also clearly mentioned for each MCU Package.
RESET Circuit
P1_29 is RESET pin by default
Typic circuit used for reset is as shown below, extracted from the development board schematic.
ISP MODE
P3_29 is ISP mode selection input by default after power up. Based on your application if ISP selection is needed, you can use a switch circuit as shown below
Programming Interface
- Following are the programming pins by default after power up:
- P0_0 – TMS/SWDIO
- P0_1 – TCLK/SWCLK
- P0_2 – TDO/SWO
- P0_3 – TDI
Please check how the programming interface is provided on the FRDM development board. In your custom board, you should handle programming pins pull up and pull down as used in the circuit below.
ADC
There is no internal reference provide in the MCU, you can use VDD or external voltage reference for the same.
MCU provides dedicated VDDA for powering the Analog section and VREFL(GND)/VREFH (VDD or VREF input) are provided to define the ADC input voltage range.
Please note if MCU is running in low voltage range at 1.8V VREFH high cannot be below 0.99V and if ADC is operating at high speed 4Msps, VREFH cannot be less than 2.4V.
P2_7 Pin can be used for external VREF Input.
RTC
MCU doesn’t have internal RTC. But, user can use timer to create RTC and related functionality easily. Still this is a limitation when you want RTC based alarm functions, hardware calendar implementation.
It will be a limitation if you want to make everything OFF and just want to keep RTC working to keep the time. In case of MCXA MCU, you will need to keep MCU powered and manage power consumption via sleep mode or use an external RTC chip.
That’s all in the hardware design overview of MCXA Microcontroller.
I my next blog on NXP MCXA Microcontroller, I will explain how you can quickly setup the development environment. what all you will need in hardware and software. So, stay tuned!
I am running an Embedded Design House, CAPUF Embedded Pvt. Ltd, located in Bangalore, India. At CAPUF, we help companies build embedded products with our hardware and firmware design services.
We also help in design optimizations for power consumption, cost, mass manufacturing, and performance.
Additionally, we develop PCB testing jigs and provide cloud-based monitoring solutions.