A 2.1-MHz crystal oscillator time base with a current consumptionunder 500 nA

A micropower crystal oscillator module for watch applications is presented. The integrated circuit is encapsulated with a 2.1-MHz crystal in a miniature vacuum package to reduce parasitic effects. The circuit comprises frequency tuning with a resolution of ±3 s/year [±0.1 parts per million (ppm)] and auxiliary circuits. A single output delivers a signal of 16 384 Hz with a frequency stability of ±2 ppm over the temperature range (-10 to 70°C). The oscillator core has two complementary active MOSFET's and amplitude stabilization in order to get both low power consumption and high stability. New coupling and biasing circuits between the oscillator and the dynamic frequency dividers allow to achieve a current consumption under 0.5 μA for a supply voltage between 1.8 and 3.5 V     

CMOS current reference without resistance

A micropower current reference in the range of 1 to 100 nA is built with CMOS transistors only, featuring low sensitivity with respect to technology and temperature. Supply voltage can be as low as 1.2 V. This autonomous circuit is simple and occupies a surface area of 0.06 mm ²     

Monolithic optical position encoder with on-chip photodiodes

A system that combines light sensors and analog and digital parts on the same CMOS chip has been fabricated. The optical and electrical properties of various photodiodes, which are fully compatible with a standard CMOS technology, are discussed. The current comparators use CMOS-compatible lateral bipolar transistors. The optical encoder also comprises a signal processor for code conversion, a serial or parallel output, and a self-test function. A 14-channel circuit which senses light signals at 880 nm with a power of 0.3-3 mW/cm² has been fabricated. Response time is shorter than 1 μs at all illumination levels. This circuit operates in the temperature range -55 to +125°C. Its current consumption is 8 mA at 5 V     

CODYMOS frequency dividers achieve low power consumption and high frequency

Frequency dividers made with complementary dynamic m.o.s. (CODYMOS) circuits require only a small number of transistors and interconnections, a single input signal and operate with a minimum number of successive transitions. This leads to a drastic reduction in stray capacitance and current consumption, and to an increase in speed. A simplified analysis of these quantities is given for binary and ternary dividers. An experimental circuit, integrated with silicon-gate technology, operates from a 1.35 V battery, divides by 3 up to an input frequency in excess of 20 MHz and draws a current of 0.4 ?A/MHz.     

Complementary dynamic m.o.s. logic circuits

Allowing both p and n channel groups of transistors to be blocked between transitions of c.m.o.s. gates leads to complementary dynamic m.o.s. circuits which, in many cases, are significantly less complex than their static counterparts. The value of the concept and a method of synthesis are demonstrated with a practical example. Systematic application to frequency dividers yields very simple new structures.