topic Re: SMBus support in MCX series in MCX Microcontrollers

SMBus support in MCX series

dav1 — Mon, 05 May 2025 20:35:17 GMT

Hi,

Going through the more simple MCX'es, especially the MCXC series for an EC/SMC like application.

I can't seem to find any clear details on how/if SMBus is supported and what version?

SMBus 2.0 is probably bare minimum, but 3.0 with higher speeds (1MHz), and then 3.1 that some more recent battery-chargers make use of (for host notify) can be handy as battery-packs become more advanced.

Would be great with some info from the MCX product team

Re: SMBus support in MCX series

dav1 — Mon, 05 May 2025 21:32:12 GMT

to give some context, here are a few recent and commonly used BMU's & chargers, all running SMBus 3.x

IC	Type	Manufacturer	SMBus Version	Features
ISL9241	Battery Charger	Renesas	3.0	NVDC, OTG, SMBus with PEC, telemetry
BQ24773	Battery Charger	Texas Instruments	3.0	Dynamic power, PEC, fast charge
BQ25720	Battery Charger	Texas Instruments	3.0	Wide input range, dual SMBus/I2C, PEC, dynamic power
MAX77960	Battery Charger	Analog Devices	3.0	Fast charging, PEC, power path control
BQ76952	Battery Monitor	Texas Instruments	3.1	Integrated balancing, PEC, high cell count support
ISL94216	Battery Monitor	Renesas	3.0	Group command, zone write, PEC
BQ40Z50-R2	Fuel Gauge	Texas Instruments	3.0	PEC, data flash, battery protection
BQ40Z80	Fuel Gauge	Texas Instruments	3.1	PEC, host notify, group command, data flash
BQ34Z100-G1	Fuel Gauge	Texas Instruments	3.0	PEC, host notify, battery management
MAX17330	Fuel Gauge	Analog Devices (Maxim)	3.0+	Group command, PEC, protection features
NCP81239	Power Delivery controller	ON Semiconductor	3.0	Telemetry, PEC, voltage regulation
LTC2977	Power System Manager	Analog Devices	3.0	Sequencing, monitoring, PEC

Re: SMBus support in MCX series

EdwinHz — Tue, 06 May 2025 16:53:26 GMT

Hi @dav1,

The MCX C series of MCUs does support SMBus, as mentioned on the "MCX C44X Sub-Family Reference Manual":

However, as mentioned on the previous table, it supports version 2 of SMBus.

BR,
Edwin.

Re: SMBus support in MCX series

dav1 — Thu, 17 Jul 2025 08:47:19 GMT

how about smbus support in the MCX A series? specifically: MCXA144VPJ

Re: SMBus support in MCX series

dav1 — Wed, 14 Jan 2026 00:54:14 GMT

reminding team NXP to reply.
lots of new MCX series parts now, but no way to filter on which parts have SMBust support

i need to be part of a charger-IC <> battery-pack that talks smbus

basically I'd like the MCX to be a passive sniffer so it can detect and read Host Notify / ARP events from the battery-pack. (preferably also run PEC decode)