Teensy 4.1 Development Board

TEENSY41_PINS Teensy USB Board, Version 4.1, With Ethernet Chip, With Pins Soldered
(Ethernet connector kit sold separately)
TEENSY41_NE_PINS Teensy USB Board, Version 4.1, Without Ethernet Chip, With Pins Soldered $33.60

Recommended Accessories: USB Cable, 8MB PSRAM, USB Host Cable, Ethernet Kit

Inventory Status:In Stock
Last physical count:Jul 9, 2024

Teensy 4.1 features the fastest micocontroller and an expanded set of powerful peripherals in a 2.4 by 0.7 inch form factor.

Teensy 4.0 can be programmed using the Arduino IDE with Teensyduino add-on.

Technical Specifications Compared 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.

FeatureTeensy 4.1Teensy 4.0
Ethernet10 / 100 Mbit
DP83825 PHY
(6 pins)
USB Host5 Pins with
power management
2 SMT Pads
SDIO (4 bit data)Micro SD Socket8 SMT Pads
PWM Pins3531
Analog Inputs1814
Serial Ports87
Flash Memory8 Mbyte2 Mbyte
QSPI Memory2 chips
Plus Program Memory
Program memory only
Breadboard Friendly I/O4224
Bottom SMT Pad Signals716
SD Card Signals60
Total I/O Pins5540


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.

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 Ethenet connection.

1   Ethernet Magjack            RB1-125BAG1A, Mouser 950-RB1-125BAG1A, Digikey 1278-1011-ND
2   Header, 3x2, 2mm pitch      Digikey 1849-1000-ND
2   Socket, 3x2, 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.