16x2 I2C Character LCD Display Module (1602 + PCF8574 Backpack, Pre-Soldered)
16x2 I2C Character LCD Display Module (1602 + PCF8574, Pre-Soldered)
A standard 1602 HD44780 character LCD with a PCF8574 I2C backpack already soldered on. Drives over just two signal wires (SDA + SCL) instead of the six GPIO the bare parallel panel needs — and there is no soldering to do.
Why the I2C version
| Wiring | Parallel 1602 | This module |
|---|---|---|
| Signal pins used | 6 (RS, EN, D4–D7) | 2 (SDA, SCL) |
| Contrast pot | External 10k required | On-board trimpot |
| Assembly | Solder a backpack on | None — ready to wire |
Key Specifications
| Specification | Value |
|---|---|
| Display | 16 characters x 2 rows, HD44780-compatible |
| Interface | I2C (PCF8574 expander) |
| Default I2C address | 0x27 (PCF8574T). Some batches use PCF8574AT at 0x3F — scan to confirm |
| Address select | A0/A1/A2 solder jumpers |
| Operating voltage | 5V |
| Logic level | 5V (use a level shifter on a 3.3V board such as ESP32) |
| I2C speed | 100 kHz standard mode only (PCF8574 limit — not 400 kHz) |
| Contrast | On-board potentiometer |
| Pins | VCC, GND, SDA, SCL |
Wiring
Arduino Uno: SDA to A4, SCL to A5. ESP32: SDA to GPIO21, SCL to GPIO22. VCC to 5V, GND to GND.
Code
Use the LiquidCrystal_I2C library (Frank de Brabander). Initialise with lcd.init(); then lcd.backlight(); — note that init() returns void, so never test it inside an if.
Notes
If the screen shows only dark blocks, adjust the contrast trimpot. If nothing appears at all, run an I2C scanner — the address is 0x27 on most units and 0x3F on PCF8574AT variants.
Ask Soldr above what you can build with this — it knows every Compoden kit this part appears in.
Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items