Teensy 4.1


The Teensy 4.1 is the latest Teensy, offering the fastest micocontroller and an expanded set of powerful peripherals.

Availability: 20 in stock

Product Code: TEENSYV41

Teensy 4.1

The Teensy 4.1 is the latest Teensy, offering the fastest micocontroller and an expanded set of powerful peripherals in a 2.4 by 0.7 inch form factor. In common with the Teensy 4.0, it can be programmed using the Arduino IDE with Teensyduino add-on. Teensy 4.1 is designed to bring all general purpose I/O pins to breadboard friendly pads on the outside edges.

While it shares many similarities with the Teensy 4.0 there are some important differences.

Teensy 4 series comparison
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


All Teensy boards are shipped assembled (without headers) and fully tested.

Teensy 4.1 & 4.0 use the same IMXRT1062, so most technical specifications are the same.


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

This is currently available only as a DIY project using this OSH Park Shared Circuit Board. PJRC is planning to offer this as a DIY kit in the near future. You can also make the connection by soldering wires.

These parts are recommended to build the Ethernet connection.

1 Ethernet Magjack  
2 Header, 3×2, 2mm pitch Digikey 1849-1000-ND
2 IDC Socket, 3×2, 2mm pitch Amphenol FCI 89361-706LF, Digikey 609-3139-ND
1 Ribbon Cable, 3 to 6 inch Digikey HF06S-5-ND
1 Capacitor, 0.1uF, 805  
1 Capacitor, 1uF, 805 probably not needed
1 Capacitor, 1nF, 805 optional, should be high voltage rated if used
1 Resistor, 1M optional
1 Circuit Board OSH Park Shared PCB


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.

USB Host

Teensy 4.1’s USB Host port allow 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. See the USBHost_t36 examples for details.


For additional specs and information, please also look at the manufacturer’s webpage – Teensy 4.1 Product Page at PJRC

Teensy Documents:

Shopping Basket
Scroll to Top