Introduction

Construction

The adapters are made up of 2 parts, obtainable separately, a top board and a bottom board.

For maximum flexibility each board is supplied as a kit of parts. The only parts soldered are the zif socket receptacle pins in the cases where the zif socket is pluggable, and the surface mount resistors, where supplied.

The bottom board can be fitted with a DIL plug for 28, 32, 40, or 48 pin sockets. Less pins may be fitted to any of these boards if required. All of the pins are connected up to the top board via 2 single-in-line connectors, and selected pins may be connected to the bottom board's ground plane.

The top board carries the device socket (PLCC, QFP, etc). Each pin of the socket is taken to a solderable pad, and to an optional pullup (or pulldown) resistor, usually 10K. The resistors are commoned to a point which the user may connect to vcc or ground as required. The board has provision for a pair of bypass capacitors. There is typically also space for a small number of resistors, capacitors or resonators, and sometimes a small i.c. The top board also has a ground plane which may be connected to any required point by the user. The board has a pair of single-in-line connectors to connect to the bottom board. Each pin on these connectors is taken to a solderable pad.

The pads are designed to be interconnected as required by the use of 30 awg Kynar insulated wire available from most electronics distributors.

After construction the boards may be plugged together to virtually conceal the wiring. Alternatively, by omiting the SIL socket strips from the lower connector, the two boards may be soldered together for a closer and more permanent adapter.

Where possible the zif socket is plugged in for easy replacement, however on some types it must be soldered. (see table below)

Tips

Pullup Resistors

Many applications require the use of pullup (or down) resistors on unused socket pins. To simplify the wiring involved we have provided every socket pin with a resistor. Depending of the board geometry these may be SIL resistor packs or surface mounted resistors. Where SIL packs are used these are supplied unfitted to allow the user to cut off the pins on resistor positions not required, before soldering to the board. In the case of surface mount resistors, as a convenience we fit all resistors. Individual resistors can then easily be removed using the tip of a soldering iron. These boards can also be obtained without the resistors fitted, at a lower cost.

Customising Service

We can also supply ready wired boards to your requirements. Please contact us for a quote.

Board Width Families

Three width families are currently available. The top and bottom boards may be interchanged within a width family as required.

Top Board Selector

Bottom Board Selector

General: This range of package converters is manufactured in England to the highest standards by MQP Electronics. Our distributors should have no difficulty in supplying you quickly with any item. Specifications of our adapters can be found on our Web Site (www.mqp.com)

If you have any difficulty in identifying the correct converter our sales office will be pleased to advise. Our phone number is +44 1666 825 666.