CMOS circuits are known for their low current consumption. This is particularly important for battery-powered circuits. Unfortunately, oscillators often require quite a bit of current. We, therefore, propose this oscillator circuit that has a very low current consumption (about 3 μA). The circuit is powered from a type LM334Z current source. The current has been set with R4 to about 3 μA. This is sufficient to power IC1 and the oscillator circuit around X1.
The oscillator generates, with the aid of a cheap watch crystal and a few surrounding parts, a signal that is subsequently applied to the divider in the 4060 and results in a frequency of 2 Hz at pin 3 (output Q13). The level of the output pulses is a lot lower than the nominal 5-V power supply voltage (IC1 is after all powered from a current source with very low current). That is why the signal on pin 3 of IC1 is amplified and inverted by T1. IC3a finally turns it into a proper square wave with acceptably steep edges.
A complementary metal-oxide semiconductor (CMOS) is the semiconductor technology used in most of today’s integrated circuits (ICs), also known as chips or microchips. CMOS transistors are based on metal-oxide-semiconductor field-effect transistor (MOSFET) technology.CMOS is an innovation used in building integrated circuits. It is used in microcontrollers, static RAM, registers, microchips, and other digital circuits.
A circuit that uses complementary pairs of p-channel and n-channel MOSFETs is called CMOS (Complementary MOS). CMOS logic ICs combine MOSFETs in various ways to implement logic functions. A logic gate composed of a single pair of p-channel and n-channel MOSFETs is called an inverter. To sum up, the CMOS circuit has the advantages of a simple structure, low power consumption, large noise tolerance, and strong temperature stability, which is conducive to high integration. In addition, due to the high degree of integration, the entire circuit is integrated into the chip.
Examples of commercial RF CMOS chips include Intel’s DECT cordless phone, and 802.11 (Wi-Fi) chips created by Atheros and other companies. Commercial RF CMOS products are also used for Bluetooth and Wireless LAN (WLAN) networks.
