ALD1108E/ALD1110E are monolithic quad/dual EPADs (Electrically Programmable Analog Device) that utilize CMOS MOSFET with electrically programmable threshold voltage. For a given input voltage, changing the threshold turn-on voltage of a MOSFET device precisely changes its drain on-current, resulting in an on-resistance characteristic that can be precisely set and controlled. Used as an in-circuit element for trimming or setting a combination of voltage and/or current characteristics, it can be programmed via a Personal Computer remotely and automatically via software control. Once programmed and set, the set
voltage and current levels are stored indefinitely inside the device as a precisely controlled nonvolatile stored charge, which is not affected during normal operation of the device, even after power has been turned off.
The ALD1108E/ALD1110E are devices built with ALD's EPAD technology, an electrically programmable device technology refined for analog applications. The ALD1108E/ALD1110E functions like a regular MOSFET transistor except with precise user preset threshold voltage. Using the ALD1108E/ALD1110E is simple and straight forward. The device is extremely versatile as a circuit element and design component. It presents the user with a wealth of possible applications, limited only by the imagination of the user and the many ways an analog MOSFET device can be used as a circuit design element. The ALD1108E/ ALD1110E do not need other active circuitry for functionality.
The basic device is a monotonically adjustable device which means the device can normally be programmed to increase in threshold voltage and to decrease in drain-on current as a function of a given input bias voltage. Once adjusted, the voltage and current conditions are permanent and not reversible. However, a given EPAD device can be adjusted many times to continually increase the threshold voltage. A pair of EPAD devices can also be connected such that one device is used to adjust a parameter in one direction and the other device is used to adjust the same parameter in the other direction.
The ALD1108E/ALD1110E can be pre-programmed with the ALD EPAD programmer to obtain the desired voltage and current levels. Or, they can be programmed as an active in-system element in a user system, via user designed interface circuitry. For more information, see Application Note AN1108.