News & Events
Xicor's Single-Chip EEPOT Replaces Four Mechanical Potentiometers
-- Device Connects Easily to Microcontrollers Via 3-Wire SPI Interface~-- Low Power Consumption Makes Device Ideal for Battery Applications
MILPITAS, Calif., February 9, 1998 - XICOR, Inc. (NASDAQ:XICO) today announced a single chip that replaces four mechanical potentiometers. This solid-state solution offers the benefits of low noise, and immunity to wear, shock, vibration, dust, oil, moisture and temperature extremes.
The X9400 can be used in a wide range of applications including set-top volume control, cell phone audio adjustments, LCD contrast controls, radio frequency tuning, laser diode bar code readers, engine controls, DVD players, etc. The chip's low voltage (down to 2.7V) and low current (1uA standby) make it ideal for battery applications.
There are three family members being announced including the X9400 with four Electrically Erasable Potentiometers (EEPOTs), the X9410 with two EEPOTs and the X9420 with one EEPOT. Each EEPOT offers 64 different resistance settings which are written (or read) via a Serial Peripheral Interface (SPI) at 2 Mbps. Since the settings are stored in nonvolatile, Electrically Erasable memory they remain even when power is removed from the devices. According to Bob Anderson, Product Marketing Manager, "The SPI interface is rapidly becoming one of the standard ways of bolting peripheral functions onto microcontrollers. This standard is so easy to use that it almost makes the design process a 'plug-and-play'' operation. With our family of EEPOTs an engineer can pick the device best suited to his application and quickly get to market using the building block approach of SPI."
Xicor's new devices use embedded EEPROM to store up to four wiper positions for each potentiometer. The sixteen, 6-bit registers that hold the wiper positions in EEPROM can also be used for general purpose nonvolatile storage.
Internally, each potentiometer consists of an array of 63 resistors connected in series. The voltage to be divided is applied across the ends of the array. By sending a command to the chip, the wiper pin can be switched to any one of the 64 resistor taps. The devices have an end-to-end resistance of 10K Ohms and each resistor in the array has a value of 158.5 Ohms.
Unlike the previous generation of EEPOTs, these new devices use CMOS transistor gates to switch the wiper to the desired tap. This approach provides a lower noise figure because it eliminates the need for an on-chip oscillator that can couple noise to the wiper output. Oscillators were used to boost the voltage driving the wiper transistors. The lower noise figure of the new devices makes them ideally suited for applications such as multimedia audio systems.
Availability and Price
The 24-pin SOIC (Small Outline Integrated Circuit) versions of the X9400 and X9410 are sampling now and will be in production in June. These two devices also come in a 24-pin PDIP (Plastic DIP) or 24-pin TSSOP (Thin Small Surface Outline Package). The X9420 will be sampling in April and will be in production in May.
Prices in 10,000 quantities for the SOIC package are:
| X9400 (4 EEPOTs) $3.25 | ||
| X9410 (2 EEPOTs) $2.45 | ||
| X9420 (1 EEPOT) $1.95 |
Company Background
Xicor, Inc. designs, develops, manufactures and sells nonvolatile in-the-system programmable products which retain information even when the system is turned off or power is inadvertently lost. Xicors product line includes digitally controlled potentiometers (XDCPs_), system management ICs, and standard and secure memory ICs .
Xicor product, corporate and financial information is readily accessible on the worldwide web at http://www.xicor.com.
