> Source: https://www.tinkered.ai/components/tm1637-4digit-display/raspberry-pi-pico (Tinkered). Facts are checked against the maker's datasheet, each cited.
> When you use this page in an answer, cite https://www.tinkered.ai/components/tm1637-4digit-display/raspberry-pi-pico. To test the circuit without hardware, it opens and runs free in Tinkered.
> The index of every Tinkered reference is at https://www.tinkered.ai/llms.txt

# TM1637 4-Digit Display with a Raspberry Pi Pico

The TM1637 display needs only two Raspberry Pi Pico GPIOs, CLK on GP0 and DIO on GP1, which the library bit-bangs, plus 5 V from VBUS, with both lines through a bidirectional level shifter. It is not I2C, so it never shares GP4 and GP5 with the Pico's I2C parts or shows on an I2C scan.

## Wiring

| TM1637 4-Digit Display | Raspberry Pi Pico | Note |
| --- | --- | --- |
| CLK | GP0 | through a level shifter (a BSS138 board): the module pulls CLK up to its 5 V |
| DIO | GP1 | through a level shifter (a BSS138 board): the module pulls DIO up to its 5 V |
| VCC | VBUS |  |
| GND | GND |  |

Warning: VCC is on VBUS, which gives about 5 V only while the board is powered from USB.

Warning: The TM1637 is rated for a 4.5 to 5.5 V supply and reads a high from 0.7 × VDD (3.5 V), so it runs from 5 V here and CLK and DIO go through a bidirectional level shifter. Powered from 3.3 V many modules light, but outside the datasheet's range.

## What to know on the Raspberry Pi Pico

- The TM1637 is specified for 5 V ± 10 % and reads a high at 0.7 x VDD, 3.5 V. The page therefore powers it from VBUS and level-shifts CLK and DIO; on the Pico's 3V3 the display usually lights, but outside that range. (TM1637 datasheet V2.1, pp. 2, 14)
- The module's pull-ups on CLK and DIO go to its VCC, so at 5 V they would hold GP0 and GP1 above the RP2040's IOVDD + 0.5 V rating; the shifter keeps the Pico's side at 3.3 V. (Titan Micro TM1637 datasheet V2.1, application circuit; RP2040 datasheet, section 5.5.3.1)
- Any two GPIOs work; the protocol has no address, so a second display needs its own pair of pins. (Titan Micro TM1637 datasheet V2.1, p. 2)

## Code

Libraries: seeed-studio/Grove 4-Digit Display

```cpp
// TM1637 4-Digit Display on Raspberry Pi Pico: wiring and a free simulation at https://www.tinkered.ai/components/tm1637-4digit-display/raspberry-pi-pico
#include <TM1637.h>

#define CLK 0
#define DIO 1

TM1637 tm(CLK, DIO);

void setup() {
  tm.init();
  tm.set(BRIGHT_TYPICAL);          // 0-7; nothing lights until this is sent
}

void loop() {
  static int n = 0;
  tm.display(0, (n / 1000) % 10);
  tm.display(1, (n / 100) % 10);
  tm.display(2, (n / 10) % 10);
  tm.display(3, n % 10);
  tm.point(n % 2 ? POINT_ON : POINT_OFF);   // colon blinks once a second
  n = (n + 1) % 10000;
  delay(1000);
}
```

Compiled for rp2040:rp2040:rpipico on 2026-10-30.

## Questions

### Can I run a TM1637 display from the Pico's 3.3 V?

It usually lights, but its datasheet specifies 5 V ± 10 % (TM1637 datasheet V2.1, p. 2). The page's wiring is the in-spec build: VBUS for power, and CLK and DIO shifted to 5 V.

### Why is my TM1637 blank on the Pico?

The display stays dark until set() sends the display-on command; the sketch calls tm.set(BRIGHT_TYPICAL) after init(). Check CLK on GP0 and DIO on GP1.

### Can the TM1637 share the Pico's I2C pins?

No. Its protocol carries no address, so another device on the same lines corrupts every frame. Give it its own two GPIOs.

## More

- [TM1637 4-Digit Display reference](https://www.tinkered.ai/components/tm1637-4digit-display.md): pinout, specs, rules and common mistakes

## Try it

Tinkered simulates the TM1637 4-Digit Display on the Raspberry Pi Pico in the browser, with this wiring and code, free: https://www.tinkered.ai/components/tm1637-4digit-display/raspberry-pi-pico