The MAX14589E/MAX14594E high-density, double-pole/double-throw (DPDT) analog switches feature Beyond-the-Rails™ signal capability that allows signals from -5.5V to +5.5V to pass without distortion even when the power supply is below the signal range. The low RON resistance (0.2Ω) makes the devices ideal for low-distortion switching, such as audio. [source: maxim-ic.com]
MAX14589E – ±5V Capable DPDT Analog Switches - [Link]
Normally one tact switch requires one digital input pin of a microcontroller. Some designs implement keypad style multiplexing to get multiple switches on fewer inputs. However, there exist other techniques that allow you to connect many switches on a single input pin of a microcontroller. This tutorial demonstrates one such technique as applied to PIC12F683 microcontroller. In this example, there are four LEDs and four tact switches connected to the PIC12F683 microcontroller. While each LED is controlled through an individual I/O pin, the four switches are connected to one ADC input pin of the PIC12F683 microcontroller.
Connecting multiple tact switches on a single input pin of a microcontroller - [Link]
rsdio writes: These chips look highly flexible for interfacing between different voltage logic circuits [via]
MAX4936, MAX4937, MAX4938, MAX4939
Octal high-voltage transmit/receive switches
Integrated T/R switches significantly reduce component count while reducing power
Integrated solution reduces system component count, saving space and improving system reliability
Consumes less system power, allowing design flexibility in ultra-portable applications
Integrated diodes protect the IC from high-voltage signals while in “receive mode”
High-voltage transmit/receive switches – [Link]
Switches and hits game @ Design news… [via]
Mark Rumreich built a puzzle for his nephew Nathan. After building a small version of the “Nathan,” he decided to ratchet up the stakes with the MEGA-NATHAN. The puzzle has a grid of 4×4 toggle switches on the face of a box. A puzzle pattern is set inside the box using a matching 4×4 switch grid. The back cover is then closed to conceal the solution from Nathan. When the front switches are set to the correct pattern, an internal buzzer buzzes, and Nathan wins. Problem is, there are 65,536 (2^16) possible switch combinations. So Mark devised a series of hints that alert Nathan to the correct solution path.
Switches and hits game – [Link]
There are six (or more) push switches. To ‘unlock’ you must press all the correct ones at the same time, but not press any of the cancel switches. Pressing just one cancel switch will prevent the circuit unlocking. When the circuit unlocks it actually just turns on an LED for about one second, but it is intended to be adapted to turn on a relay which could be used to switch on another circuit.
Simple Electronic Lock Project - [Link]