Leading Edge LEP-95081SX/25

Leading Edge LEP-95081SX/25

Preliminary Information
Release Year	1993 or 1994
Leak Risk	High
Batteries	Removable Ni-Cd primary battery, internal lithium TL-5186 CMOS battery
Destructive Entry	No
Hardware Specifications
CPU	Intel 80386SX @ 25 MHz
Memory Capacity	Up to 8MB
Memory Type	Proprietary expansion connector with 2MB on board. Uses GM71C4400ALJ or equivalent DRAM chips.
Storage	2.5" IDE HDD, 3.5" Floppy
Graphics	Chips & Technologies F65520 VGA
Display Interface	Internal LCD and VGA
Sound	Piezo speaker
Power Requirements
Input Voltage	12V DC
Current (Amps)	2A

This is a low-end laptop made around 1993 or 1994. It features a monochrome passive matrix display and internal VGA graphics using a Chips & Technologies F65520. I/O ports include one each of PS/2, 25-pin parallel, 9-pin serial, 15-pin VGA, and an RJ-11 modem on some models.

Known Issues

Will not power on, power supply LED just flashing

Causes

• Shorted electrolytic capacitor in the internal DC-DC power supply causing the power supply crowbar circuit protection to activate.

Solutions

• Recap the DC-DC power supply.

Disassembly Notes

Disassembly is mostly straight forward with no hidden screws. Screws are all #0 Phillips except for the posts next to the I/O ports, which need to be removed as part of the disassembly.

Original Parts

Internal DC-DC power supply

Capacitor Specifications and Footprint Information

Qty	Capacitance	Voltage	Mount	Diameter/Size	Height	Lead Spacing	Temp	Type	Brand
1	330 µF	16	Through Hole	8 mm	12 mm	4 mm	85 °C	Electrolytic	Samsung
2	1000 µF	6.3	Through Hole	8 mm	12.5 mm	4 mm	105 °C	Electrolytic	Samsung
1	0.33 µF	50	Through Hole	5 mm	11 mm	2 mm	85 °C	Electrolytic	Samsung
2	47 µF	50	Through Hole	6 mm	11 mm	3 mm	105 °C	Electrolytic	Samsung
3	100 µF	16	Through Hole	5 mm	11.5 mm	2 mm	105 °C	Electrolytic	Samsung

Note: tolerance for the diameter of the capacitors is tight on this circuit board, especially for the 1000 µF capacitors.