Lights charger

Boards / 6S to the 2S lighting battery, LT3652 2 A CC/CV

The lights node's charger: takes the 6S flight pack and charges the 2S lighting battery at up to 2 A, only when the node enables it.

Revision: A draft
Sheets: 1
Parts: 19
Location: aircraft
Bus: none: a GH-6 lead and a charge pair to the lights node
Status: Withdrawn 2026-10-11: the dock charges the lighting battery instead

What it does

Withdrawn. Drawn and withdrawn on 2026-10-11: at 2 A the charger would make about 2 W next to the LiPo with nowhere to shed it, so Ryan moved charging to the dock, which charges the lighting battery through two contacts on the keels while the lights node guards the input. The page stays as the record of the design.

It charges the lighting battery from the flight pack. An LT3652 charges at constant current, then constant voltage: 2 A up to 8.38 V, ending at a tenth of the current. It eases off before it drags the flight pack below 3 V a cell. It charges only while the node holds its enable line high, and an unplugged lead means no charge. The fused 6S also goes to the node, so an empty lighting battery does not stop the node from starting a charge.

The circuit is the lights node’s charger as it was, moved to its own board on 2026-10-11 so the node fits its seat. It carries steady current and none of the strobe pulses, so it can sit some distance from the node.

Where it sits

Over the lighting battery, about 90 to 100 mm from the node. th-blender is measuring the seat; the board is about 22 x 20 x 7.5 mm (estimate).

Main parts

Part	Function
LT3652	2 A charger, 6S to 8.38 V
Littelfuse NANO2 3 A, SMBJ33A	Fuse and surge clamp on the 6S lead

Connections

Connector	Type	To
J1	Solder pads, 20 AWG pigtail to an XT30	6S tap at hub A or B
J2	GH-6	Lights node J1: fused 6S, the charger’s enable and status
J3	Solder pads, 22 AWG	Lights node J15: the charge current

Status

Rev A draft, schematic only, 19 parts (2026-10-11). ERC gives 0 warnings and 1 waived error (the charger’s timer pin is tied to ground on purpose, which selects the tenth-of-current end of charge). No layout yet.

Schematic and layout

Files

lights-charger.kicad_sch

From the EDA repository at revision b201257 (2026-10-12). Open the files in KiCad 10 or later.