iPad Logic Board and Model Number Reference List

Here is a list of Apple iPad logic boards and corresponding models

iPad 1 820-2740
iPad 2 820-2875
iPad 2 820-3069
iPad 3 820-2996
iPad 4 820-3249
iPad Air 2 820-3633
iPad Air 2 820-4550
iPad Air 820-3508
iPad Mini 2 820-4124
iPad Mini 820-3243
iPad Charger Circuit Diagram

I’ve pieced this together from all over the place – please let me know if there are any errors or corrections.

EDS, Inc LeakSeeker 89

LeakSeeker 89 PCB

EDS, Inc LeakSeeker 89 PCB

Awhile back I was reading through a back issue of Nuts & Volts magazine and came across an ad for the LeakSeeker 89 from Electronic Design Specialists. I was intrigued by the device and searched for a place to buy one, even a used one, but they were nowhere to be found. This led me to contact Dave Miga and order a parts kit. The kit price was reasonable for not having to source parts and deal with minimum order quantities plus he is the only source for the programmed PIC microcontroller.

LeakSeeker 89 Auto-ranging Fault Locator PCB

The LeakSeeker 89 locates the exact spot on the PC board (to within a fraction of an inch) where a shorted or leaky component is bringing a power supply bus or data line to ground. It is the only locator that can locate defects from zero to 300 ohms with no loss of resolution. It can even find active shorts that a DVM won’t even show. The high GAIN mode can locate shorted components on multi-layer boards with ground planes and a power layer.

After ordering the parts, Dave emailed me the bill of materials, enclosure overlays, Gerber files to get the PCBs manufactured. Not wanting to pay the suggested $100 for 5 PCBs, I invested some effort into converting the Gerbers into standard format and getting them ready for manufacturing at a place like EasyEDA or OSH Park. EasyEDA was the cheapest and OSH Park, though high quality and quick, was expensive.

So, having the parts and PCBs arrive, I began construction. Keep in mind, there are no assembly instructions at this time. (I’ll update here if I develop some.) It took me about two hours to get a finished product minus the enclosure (I’m waiting for it to arrive).

Assembly is pretty straightforward with typical through-hole components. The only issue I had was installing the BR2 rectifier backwards since it is not obviously marked (the square pad is the + pin).

I haven’t had an opportunity to use the LeakSeeker yet, but, after some basic tests, it appears to function.

The next steps are to get the case, drill it for the LEDS, switches, and probes, then make and apply the overlays. Dave provides all of the dimensions needed to ensure a quality completed product.

Here is the finished product in a poorly labeled case:

Finished LeakSeeker 89

Finished LeakSeeker 89



Parts Kit: EDS, Inc – last paragraph on the page explains how to order.
PCB: These are for sale through a few outlets. The best price will be at the Eccentric Workshop store, but they are on Tindie and eBay.
Enclosures: OKW Tenclos Pulpit 590.9 – these are imported from Italy and you must email the company to order (I worked with Jeff Duchess). If there is enough demand, I may stock these.


Order from OSH ParkI sell on Tindie

Market Monday: TEquipment.net

TEquipment.net has turned out to be a great supplier of electronic test equipment and tools. I ordered my oscilloscope from them and initially had some issues. Their customer service was far better than any company I have dealt with before – they reached out to me to fix the problem and followed through on it.

They carry a wide range of test equipment from a wide range of brands. They also sell 3D printers, lab equipment, various environmental testers, thermal images, and soldering equipment. I will check with them first when I pick up a power supply, soldering supplies, and other equipment.

If you are shopping for electronic test equipment, check out TEquipment.net.

Rigol Oscilloscope

I recently purchased my first oscilloscope, a Rigol DS1054Z. What sold me on this one is the built in protocol decoding and the ability to be unlocked. Out of the box, this is a 50 MHz, 4-channel scope capable of 1 GS/s sampling for just under $400.

It just so happens that these Rigol scopes can be unlocked with a little bit of software (enter your serial number, DSER, and click Generate). This unlocking ups it to 100 MHz of bandwidth, expands the memory from 12 Mpts to 24 Mpts, unlocks some advanced triggers, unlocks the decoders, and unlocks the recording feature.

The advanced triggering and decoding supports RS-232/UART, I2C, SPI, Runt, Windows, Nth Edge, Delay, and Time Out.

Rigol scopes also have full control over USB or ethernet. They come with what appears to be decent software but are also widely supported in other applications. There is support, via VISA, for LabView, Excel (VBA), MatLab, Sig-Rok/PulseView, etc.