Teensy 4.1 with Ethernet

PJRCSKU: 102653
Sale price £29.90
incl. VAT
excl. VAT
In stock

Awesome Extras

PJRCEthernet Kit for Teensy 4.1
Sale price £3.70 incl. VAT excl. VAT
PJRCPSRAM Chip for Teensy 4.1
Sale price £3.70 incl. VAT excl. VAT
SanDiskSanDisk MicroSD Card (Class 10 A1)
Sale priceFrom £6 incl. VAT excl. VAT
SparkfunSparkFun Qwiic Shield for Teensy - Extended
Sale price £5.70 incl. VAT excl. VAT

Teensy 4.1 with Ethernet chip features the fastest microcontroller and an expanded set of powerful peripherals in a 2.4"x0.7" form factor and can be programmed using the Arduino IDE with Teensyduino add-on.

We also stock a version of this board without the Ethernet chip (a workaround for the pesky chip shortages!) which is slightly cheaper - handy if you have no use for the Ethernet functionality.

We also sell the Teensy 4.1 with pre-assembled headers (great for those who don't enjoy soldering!)

Comparison to Teensy 4.0

Teensy 4.1 & 4.0 use the same IMXRT1062, so most technical specifications are the same. Please refer to the Teensy 4.0 page for common specifications and features.

Feature Teensy 4.1 Teensy 4.0
Ethernet 10 / 100 Mbit
DP83825 PHY
(6 pins)
USB Host 5 Pins with
power management
2 SMT Pads
SDIO (4-bit data) Micro SD Socket 8 SMT Pads
PWM Pins 35 31
Analog Inputs 18 14
Serial Ports 8 7
Flash Memory 8 Mbyte 2 Mbyte
QSPI Memory 2 chips
Plus Program Memory
Program memory only
Breadboard Friendly I/O 42 24
Bottom SMT Pad Signals 7 16
SD Card Signals 6 0
Total I/O Pins 55 40


Teensy 4.1 is designed to bring all general-purpose I/O pins to breadboard-friendly pads on the outside edges.


To use the Ethernet port, a magjack and capacitor need to be connected.

We have the PJRC Ethernet kit available here.

Memory Expansion

The bottom side of Teensy 4.1 has locations to solder 2 memory chips

The smaller location is meant for a PSRAM chip. The larger location is intended for flash memory.

The PSRAM chip is meant to be soldered to the smaller pads on the bottom side of Teensy 4.1, underneath the SD card socket, between pins 31-32 and 33-34. Do not use the larger pads. A single PSRAM chip must be soldered to the smaller pads to be detected.

USB Host

Teensy 4.1's USB Host port allows you to connect USB devices, like keyboards and MIDI musical instruments. A 5 pin header and a USB Host cable are needed to be able to plug in a USB device. USB hubs may be used if more than 1 device is needed.

Revision History

As of 03/04/2024 we are no longer including header strips with our Teensy boards.

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