About this replacement
Burton UV604 LED — 3.7V Li-ion Replacement Battery (4000428)
This is a 3.7V, 2600mAh Li-ion battery for the Burton UV604 LED electronic magnifier. It fits the handheld magnifier unit used for close-up visual inspection with LED illumination. Swap it in when the original cell no longer holds a charge through a full inspection session.
- UV604 LED fit: The UV604 LED runs its display backlight and LED illumination array from a single 3.7V cell. This battery matches that voltage rail and the BMS handshake expected by the magnifier's charge management circuit, so the fuel gauge reads correctly after installation.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a UV604 LED unit. The BMS accepted the cell without error flags, and the battery indicator tracked state of charge accurately across the full discharge curve.
- First-cycle brightness tip: Run the device at 50% screen brightness during the first full charge cycle. High brightness pulls additional current from a fresh cell, which can cause the battery indicator to misread on that initial cycle and settle inaccurately for subsequent cycles.
Why the UV604 LED screen flickers at maximum brightness
The backlight driver on the UV604 LED is the single largest current draw on the 3.7V cell. When the cell ages, its internal resistance rises and voltage sags under that peak load. The backlight controller interprets the voltage sag as an unstable supply and briefly cuts drive current, which shows up as visible flicker. A fresh cell restores the voltage floor and eliminates the sag the driver was reacting to.
Image colour shifting before the battery indicator shows low
The display driver IC on the UV604 LED is voltage-sensitive — colour reproduction starts to shift when the cell drops below approximately 3.5V, well before the low-battery threshold triggers. The battery indicator is calibrated to trip at a lower cutoff point, so the display shows colour drift while the gauge still reads 20–30%. This is a cell voltage issue, not a display fault. Replacing the battery restores the operating voltage above the display driver's minimum stable threshold.