the Home

This product group caters to needs around the home (ICs for security, audio, video, and home automation are typical). Here are links to the descriptions of all the ICs in this group:

Cameras and Camcorders

These circuits add functionality to your cameras and camcorders. The ELM303 and the ELM624 both use the LANC standard to talk to camcorders and some still cameras, while the ELM307 was created with only still cameras in mind.

Please note that we do not keep a database of cameras and their protocols. You may be able to find information on the web to help you decide if one of our products will work with your camera.

ELM303 – Camcorder Time-Lapse Control
This circuit periodically powers up a camcorder, instructs it to record either 1 or 10 seconds of video, then powers it down again. Programmable for delays of 10 minutes to 24 hours. Requires a camera with a Control L (LANC) port and a power control pin. Handy for those Science Fair projects, or for security surveillance.

ELM307 – Camera Control
Trigger your still (film or digital) camera from various sources including lightning (using an AM radio), a light beam, an alarm circuit or a momentary switch. A single pushbutton is used for power on/off as well as mode switching, keeping the interface simple.

ELM624 – Control L (LANC) to RS232 Interpreter
Control L or LANC is a standard interface for controlling audio and video devices. It is similar in some ways to RS232, but not enough to allow direct connection to your computer. By using the ELM624, the peculiarities of the interface are translated for you, allowing direct control and monitoring of your favourite A/V machines.

Several people have asked about the ELM624 and the newer ACC interface. While this is very similar to LANC, it is not quite the same. This version of the ELM624 is not able to initiate an ACC connection, and can not automatically send the periodic messages needed to keep the connection alive.


A couple of handy circuits. They perform the core functions for you, so you can concentrate on other things.

ELM334 – Garage Doorman
This IC was designed to remotely show the position of a garage door, but it can be used to monitor almost any electrical contact. A simple two wire connection is all that is needed to remotely show position using red and green LEDs, and with the addition of only a few transistors these same two wires can also be used to control an output for operating an electric garage door opener, reset a circuit, or generate an alarm. This one is particularly handy for late at night when you’re not sure if you closed the garage door or not.

ELM365 – Security System Controller
All the basics for a home security system, in one 8 pin package. This integrated circuit provides delayed and immediate operation as well as automatic alarm reset after five minutes. Both pulsing and steady outputs are provided for driving a variety of alarm devices. Buy many and create a multizone system!

Stepper Motors

If you’re interested in experimenting with stepper motors, these integrated circuits may be of use to you. These only provide the core logic functions needed for motion control, and you will still need to build the power supply, the high power motor drive circuit, and the control circuit, but it’s a start.

ELM310 – Stepper Motor Controller
One of the messiest parts of getting started with stepper motors is creating the up/ down counters to drive the motor phases. This chip does all of that work for you, so that all you have to supply is a direction and a step input. The ELM310 provides dual modes of operation, easily switching between half-stepping and full-stepping modes, while also providing very high speed bidirectional operation.

ELM311 – Stepper Motor Controller
This IC is similar to the ELM310, but only supports the single phase full-stepping mode of operation. This is useful if you only plan to use one mode.

ELM312 – Stepper Motor Controller
This IC is like to the ELM310 as well, but only supports the half-stepping mode of operation. Again, this is useful if you only plan to use the one mode.

ELM313 – Stepper Motor Controller
This chip is almost the same as the ELM311, operating only in the full-step mode, but it always energizes two phases at a time in order to produce more motor torque.


A couple of handy circuits if you want to cause an action should a temperature change beyond a set point, or if any resistance changes beyond a set point, for that matter.

ELM331 – Solid State Thermostat
Basically a resistance comparator, this device monitors the resistance of a standard (inexpensive) NTC thermistor, compares it to a reference, and provides a control output depending on the relative values. Proportional hysteresis is provided to reduce hunting.

ELM341 – Low Power Thermostat
Very similar to the ELM331, this IC switches to standby mode between temperature measurements, to reduce power consumption. This is convenient for designs that may be required to operate on a backup battery supply for extended periods of time.


Slowly varying signals (like that from a light dependent resistor) are difficult to interface to many circuits. Typically you need a schmitt trigger circuit to eliminate jitter as the signal passes through the setpoint, as well as some timing logic to ensure that the circuit is not simply responding to a fast noise pulse. This circuit provides those functions and more.

ELM337 – Light Switch
An easy way to interface to light dependent resistors, or photocells. One external resistor sets the threshold point, and internal circuitry provides line frequency filtering, hysteresis, and delay on pickup and dropout of 1 msec to 10 minutes.