A highly stable CMOS Self-Compensated Oscillator (SCO) based on an LC tank temperature Null concept

Temperature- and Supply Voltage-Independent Time References for Wireless Sensor Networks

“…3. 3 The response of an oscillator to an injected noise current can be modeled using two single-input, single-output systems, one for the excess phase and one for the instantaneous amplitude . .…”

“…Using the timing information, the location of the different tags and/or HUBs can be resolved. 3 Furthermore the data can be saved, analyzed or connected to the so-called internet of things (IoT).…”

A CMOS LC-based frequency reference with ±40ppm stability from −40°C to 105°C

“…On the other hand, the SCO utilizes the TNULL phenomenon by forcing the LC tank to operate around ϕ NULL yielding Δf TC of only tens of ppms [11].…”

“…Pure CMOS LC-based SCO has been introduced in [11]. The SCO has demonstrated ±50ppm frequency stability across the temperature range (-20-70°C) [3] and ±100ppm across (-40-85°C) [10].…”

“…1 depicts that any standard CMOS LC tank has a specific operating phase at which the temperature dependence of the tank impedance decreases dramatically. This phenomenon is denoted as the Temperature Null (TNULL) phenomenon and that specific phase at which the temperature dependence is minimized is denoted as ϕ NULL [11].…”