This breadboard can be used for temporary prototypes and experimenting with circuit design more easily. It is designed for prototyping circuits on chips in DIP-packages and discrete components. The breadboard is intended primarily for prototyping devices on microcontrollers AVR (ATMega8/48/88/168/16/32/8535/...) and АТ89Сх50. The breadboard is based on 40-pin single row connectors PBS (step 2.54mm) and IC-sockets. It looks as follows:
The first PCB is intended for mounting chips. IC-sockets are arranged in 5 rows: the first two rows of 5x DIP-16, the thrid row - 4x DIP-20, fourth row - 2x DIP-28 + 3x DIP-8, last row - 2x DIP-40. The upper socket DIP-20 intended for microcontrollers AT89Cx51, the upper socket DIP-28 - for MC ATMega8/48/88/168 and similar in pinout. The bottom socket DIP-40 intended for MC series ATMega16/32/8535/8515. For these three panels can be connected by jumpers the power supply, RESET pin, crystal oscillator with capacitors, UART-connector and ISP-programmer. The other sockets can be connected/disconnected power and ground pins. As jumpers I used parts of PLS-connector.
The second PCB is intended for discrete components. It contains six vertical rows of three-slot PBS and also one PBS on the top (power supply +5V) and one BPS on the bottom (ground). In addition there are the following boards:
All this "periphery" is connected to two horizontal slots of PBS-40 at the top of the main board. Jump wires with plugs (from PLS-connector) soldered to the wire ends used to solderless breadboarding.
For converting the interface signals TTL <-> RS-232 is used MAX232. The converter is designed as plug to a DB-9 serial connector and is powered from the power board.
The circuit of the voltage regulator is shown below. To jack Х1 connects a source of unregulated supply (AC or DC) which regulated up to 5V. If a tested device is powered by antoher voltage, an alternative power supply can be connected to the Х2 jack. The switch power is connected to the terminals SB1.1 and SB1.2. Experience using this breadbord shows that here also be useful to add some button (with normally closed contacts) to reset a microcontroller. Also on this board is installed the USB connector (would also be helpful to add here a couple 3.3V zeners and resistors for USB signals converting).
Buttons are connected in groups of three. I do not show there circuits for buttons and LEDs, but it can be downloaded from the link below. You can also download all the other circuits and PCB layouts (main board - for SprintLayout, others circuits and boards - for Eagle).
Files: Circuits and PCBs