Teensy 4.1 With Ethernet + Header Strips

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.

Free headers!

We now include free headers with all of our unsoldered Teensy boards! This board comes with two 36-way header strips for you to cut down and solder.

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)	-none-
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

Pinouts

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

Ethernet

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.