# Automatic voltage source, lowering/raising, 0.5-30V, with LCD

> Automatic voltage source ZL-SJVA-4X, buck-boost type, with adjustable output 0.5-30VDC and adjustable current (limit set via CC potentiometer) for constant current mode. Supply voltage 5.5-30VDC, output current 3A (4A with active cooling), output power 35W (50W with cooling). LCD display shows input, output voltage and current, reverse polarity and short-circuit protection, ON/OFF push button control. Can be used to power projects, LEDs or charge batteries.

- Page: https://sigmanortec.ro/en/automatic-voltage-source-lowering-raising-05-30v-with-lcd
- Price: 71.63 RON
- Availability: In stock; 1-2 zile
- Reference: 9119 · EAN: 5943580898269
- Category: Electronic components > Other Tension Modules
- Specifications: Minimum Output Voltage: 0.5; Maximum Output Voltage: 30; Source Type: Automatic; Voltage Adjustment: Yes; Adjustment Type: Variable
- Package (shipping data): 0.067 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 04:49 (Europe/Bucharest)

## Description

The automatic power supply raises or lowers the voltage, ideal for powering projects, LEDs or charging batteries. It offers adjustable output 0.5-30V and adjustable current limiting for constant current mode, LCD display for input voltage, output and current, reverse polarity and short circuit protection, ON OFF button control.
Automatic voltage source, can be used both as a voltage raiser or a voltage reducer, adjustable voltage, adjustable current (limit setting by potentiometer), output voltage between 0.5 and 30VDC.
LCD display with input voltage, output and output current.
Power polarity protection, protects the module from burning when the power supply is accidentally connected.
Anti-intrusion output, protects battery charging.
On/Off control from the ON/OFF button.
Specifications:
Model: ZL-SJVA-4X
Supply voltage: 5.5 - 30VDC (at 5V the displayed values may be erroneous, at 4.7V the low voltage protection enters)
Output voltage: 0.5 - 30VDC
Output current: 3A maximum, adjustable, 4A with active cooling
Output power: 35W without cooling, 50W maximum with active cooling
Voltage display resolution: 0.05V
Current display resolution: 0.005A
Conversion efficiency: 88%
Soft-Start: Yes
Polarity protection: Yes
Anti-intrusion output: Yes
Short circuit protection: Yes
Operating frequency: 180KHz
Dimensions mm: 66 x 48mm
Functions:
The module has two buttons: IN/OUT for switching the display between the input and output voltage. ON/OFF for On/Off.
DC potentiometer for current regulation, once the load reaches the set current, it enters constant current mode.
CV potentiometer for voltage regulation.
Instructions for use:
Used as a voltage booster module:
- Adjust the voltage in the CV potentiometer (you can see it on the display while adjusting).
- Measure the current at the output terminals with a multimeter and adjust the DC potentiometer to the desired value.
Used in this way, the output voltage can have a drop of 0.2V.
Used as a battery charger:
- Due to the constant current function, the accumulators will be constantly charged with the same current.
- Set the charging voltage (example for 3.7V lithium, set the voltage to 4.2V).
- Set the maximum charging current to the required value, usually 0.5C or 1C (for example, with a 2000mAh battery, you can safely charge with 0.5C, i.e. 1Ah), using a multimeter.
- Connect the battery.
Used as a source for LED
Video: