Product Identification

Depending on the location of the label there are different ways to identify the USB-SD-Mux.

The serial number and hardware revision are also part of the USB identification and can be used to distinguish multiple USB-SD-Muxes connected to one host computer. See Reliable Names for further reference.

Hardware Generations

There are two major USB-SD-Mux hardware generations, the USB-SD-Mux Classic and the USB-SD-Mux FAST:

USB-SD-Mux Classic

This is the first generation of USB-SD-Mux devices. Up until mid-2024 this was the only kind of USB-SD-Mux and thus just called "USB-SD-Mux". The "Classic" denomination was added in retrospect.

This USB-SD-Mux has a micro USB connector and lacks the familiar rocket penguin logo on the PCB.

It can also be identified by the P01-R04… marking on the PCB and the rev4 / usb_sd_mux-S01-R04… labels on the device / box.

USB-SD-Mux FAST

This is the second generation of USB-SD-Muxes, which is optimized to work with faster SD-cards and devices.

This USB-SD-Mux has a USB-C connector and a rocket penguin logo on the micro SD card stub.

It can also be identified by the usb_sd_mux-P03… marking on the PCB and the usb_sd_mux-S03… labels on the device / box.

This manual follows a convention of using just "USB-SD-Mux" when referring to either variant and adding "Classic" and "FAST" when referring to one of the variants.

Label on the Package

The label on the package has changed with the batch in May/2021, therefore you can either find a small label on the front of the packaging or a larger label on the bottom of the packaging.

Small Label on the front side

Example for a small USB-SD-Mux product label

You can identify the revision of your device by the revision-string on the label on the packaging. An example of such a label is shown on the right.

The information on the label is formatted as follows:

                           SN: 000001
usb-sd-mux-S01-R04-V02-C01
                           ^^^^^^^^^^ - serial number
           ^^^^^^^^^^^^^^^ ------------ hardware revision
^^^^^^^^^^ ---------------------------- product identification

Large Label on the bottom side

Example for a large USB-SD-Mux product label

The example serial number SN: 00002.00001 indicates it is the first instance in product class 00002 (USB-SD-Mux).

The revision string usb_sd_mux-S01-R04-V02-C02 decodes to:

• usb_sd_mux - Product

• S01 - PCBA design

• R04 - Device revision

• V02 - Assembly variant

• C02 - Changes done after product release

Label on the Device

We have changed the manufacturer between the USB-SD-Mux Classic and FAST. In this process the labeling on the device has also changed.

Label on a green PCB

If your USB-SD-Mux has a green PCB it is a USB-SD-Mux Classic. The label decodes as follows:

USB-SD-Mux
rev. 4   Nr. 0987

             ^^^^- Serial number
^^^^^^ ----------- Short form of the revision

The short form of the revision can be matched to the long revision as follows:

Short form          Full revision
----------          -------------
[no revision given] usb-sd-mux-S01-R02-V01-C00
rev. 4              usb-sd-mux-S01-R04-V02-C01, usb-sd-mux-S01-R04-V02-C02

Label on a black PCB

If your USB-SD-Mux has a black PCB it is a USB-SD-Mux FAST. All devices are build from the following revision: usb-sd-mux-S03-R02-V01-C00.

Product Changelog

During development of the USB-SD-Mux multiple releases have been done. This chapter lists the differences between these versions:

usb-sd-mux-S03-R02-V01-C00 (USB-SD-Mux FAST)

New faster SD card data line switch and addition of two digital outputs.

usb-sd-mux-S01-R04-V01-C02 (USB-SD-Mux Classic)

Replaced LEDs with new types.

usb-sd-mux-S01-R04-V01-C01 (USB-SD-Mux Classic)

Initial product release. Re-design to cope with EMC.

usb-sd-mux-S01-R02-V01-C00 (USB-SD-Mux Classic)

Pre-Release. This version has been shipped to some partners for evaluation.