Specifications
| Type | Infrared LED driver: an infrared LED and a red indicator, switched together by an NPN transistor. SIGNAL HIGH turns them on |
|---|---|
| LED | Everlight IR333C-A, 5 mm, standing on the board and pointing away from it. Peak 940 nm, rated 100 mA continuous |
| Beam | 20° across: half intensity 10° either side of straight on. Half the width of the TK16's |
| Drive | About 13 mA from 3.3 V on VCC, 24 mA from 5 V, set by a 150 Ω resistor. Worked out, not measured |
| SIGNAL | 1 kΩ into an S8050's base, and nothing else. It takes about 2.6 mA from a 3.3 V pin. No pull-down: set the pin LOW first |
| Supply | 5V for the most range (VBUS on a Pico), or 3V3. VCC only feeds the LEDs and never reaches SIGNAL, so 5V is safe on a 3.3 V board |
| Current | About 27 mA from 5 V while on, 14 mA from 3.3 V; nothing while off |
| Carrier | None on the board. A TK15 receiver needs 38 kHz bursts: send them with IRremote or micropython_ir |
| Indicator | Red LED and 1 kΩ on the same transistor: lit exactly when the infrared LED is on |
| Pins to wire | 3 of the 4: GND, VCC and SIGNAL. NC is connected to nothing on the board |
| Header | 4-pin right-angle male, 2.54 mm pitch: GND, VCC, NC, SIGNAL, with GND on the square pad |
| Board | 22.4 × 30.4 mm, two 4.8 mm mounting holes 16 mm apart. The front prints ACTIVE HIGH, the back EMITS INFRARED LIGHT |
| In the box | 1 × TK63 block. It also ships in the TinkerBlock 46-piece kit |
What it does
It sends infrared light when your board says so. The 5 mm LED standing on the board shines at 940 nm, which you cannot see and which remote-control receivers, phototransistors and many phone cameras can.
Your pin does not light it. SIGNAL goes through 1 kΩ into an S8050 transistor, and the transistor lets VCC push the LED's current through a 150 Ω resistor: about 13 mA from 3.3 V and 24 mA from 5 V. A red LED on the same transistor lights whenever the infrared one is on. It is the TK16 IR Sender's circuit, part for part, with a narrower 5 mm LED.
The page this replaces called it an LED and its resistor lit by the pin, said the resistor was sized for safety rather than distance, suggested an external transistor for more range, and sent remote-control projects to the TK16. The transistor is on the board, the LED runs at a quarter of its rating from 5 V, and this block sends remote codes as well as the TK16 does.
Two things to know before wiring
- VCC may be 5 V on any board. It only feeds the LEDs and never reaches SIGNAL, and 5V gives the most range. VBUS on a Pico.
- A remote-control receiver needs a carrier. Nothing on the board makes one. A steady HIGH is invisible to a TK15; IRremote makes the 38 kHz.
Wiring, in four lines
- GND to your board's GND.
- VCC to 5V, or VBUS on a Pico. 3V3 works, with less range.
- SIGNAL to GPIO 6 on an ESP32-S3, GPIO 22 on an ESP32, D3 on an Uno, GP17 on a Pico.
- NC to nothing: it is connected to nothing on the board.
Then pinMode(pin, OUTPUT), digitalWrite(pin, LOW) first, and HIGH turns
it on.
Where to start
The handbook below is nine short articles, each with a working figure. The first blink is three wires and a phone camera. A carrier the TK15 hears sends real remote-control frames, and a beam you can break pairs it with a TK64.
For how it works, read the pin only opens the gate and five volts is allowed here. If nothing sees it, when nothing sees it.
When it doesn’t work
- How do I know it is on? I cannot see anything.
- Watch the small red LED: it is on the same transistor, so it lights exactly when the infrared LED does. Then look at the infrared LED through a phone camera in a dim room; many show 940 nm as a faint violet glow, and some filter it out.
- Can I put VCC on 5V with an ESP32 or a Pico?
- Yes, and it gives the most range. VCC feeds only the two LEDs; your pin drives the transistor's base through 1 kΩ, and VCC never reaches it. On a Pico, VBUS is 5 V while it is on USB.
- Will it control my television?
- It can, the same way the TK16 does: IRremote sends the 38 kHz carrier and the code. A steady HIGH does nothing to a remote-control receiver. Capture your remote's code with a TK15 first.
- What is the difference from the TK16 IR Sender?
- The LED. The circuit is the same part for part, with the same pins and sketches. The TK63 has a 5 mm LED standing up with a 20° beam; the TK16 a flat sidelooker with a 40° beam. Aim the TK63; the TK16 is more forgiving.
- How far does it reach?
- That depends on the receiver, the aim and the room more than on this block. With VCC on 5V the LED gets about 24 mA, a quarter of its rating, and about a third more reach than from 3.3 V. Keep bright light off the receiver.
- Can I make a break-beam with it?
- With a TK64, which sees steady infrared. Read the TK64 with the TK63 off, then on, and keep the difference: that cancels the room's own infrared. The handbook's break-beam article does exactly this.