# Power Supply, 220VAC to 4.2V, Lithium charger, 5.5x2.1

> Switching power supply from 220VAC (100-240VAC, 50-60Hz) to 4.2VDC, 1A, for charging 1S Lithium-Ion batteries. Maximum power 4.2W, 1 meter cable terminated with a 5.5x2.1mm DC plug, center positive polarity. Intended for integration into electronic projects, not for finished consumer products.

- Page: https://sigmanortec.ro/en/power-supply-220vac-to-42v-lithium-charger-55x21
- Price: 20.57 RON
- Availability: In stock; 1-2 zile
- Reference: 7754021 · EAN: 5946217210120
- Category: Electronic components > Battery > Battery Chargers
- Specifications: Technology: Lithium Ion; Load voltage: 4.2VDC; Number of cells: 1S; Input Voltage Type: AC; Output Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.
- Package (shipping data): 0.072 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 05:45 (Europe/Bucharest)

## Description

Switching adapter 220VAC to 4.2V DC, 1A, ideal for charging 1S Li-Ion batteries up to 4.2V. It offers stable and efficient power supply, has a 1 m cable and a 5.5x2.1 mm DC male plug with positive center, suitable for integration into electronic projects and assemblies.
Universal power adapter with output voltage of 4.2V and current of 1A, powered by 220VAC, ideal for charging Lithium-Ion batteries to a final voltage of 4.2V.
It works with a switching power supply, which ensures high efficiency and power stability.
The cable is 1 meter long and ends with a 5.5x2.1mm.
Product intended exclusively for integration into electronic projects. It is not a charger for finished consumer products. Recommended use only for people with basic technical knowledge in electronics.
Specifications:
Input voltage: 100-240V AC, 50-60Hz
Output voltage: DC 4.2V
Battery Compatibility: Lithium-Ion
Battery Configuration: 1S
Output current: 1A
Maximum power: 4.2W
Cable length: 1 meter
DC jack: 5.5x2.1mm
Polarity: center positive, outside negative
Use:
Check the compatibility of voltage and current between the adapter and the powered device or battery to be charged. This power supply can charge a 1S battery or battery pack with a constant current of 1A.
Connect the adapter to a wall outlet with a voltage between 100 and 240V.
Insert the DC connector into the corresponding port on the device.
Do not use the adapter for equipment that requires more power than that provided (1A), to avoid overloading.
Unplug the adapter from the outlet when not in use to prevent unnecessary energy consumption.