A NETWORK ANALYZER QCM SHIELD

Just like with the Q-1, the primary component of the openQCM NEXT electronics is a network analyzer. This device passively interrogates the quartz sensor by sweeping around its resonance frequency.

The actuation signal is produced by the AD9851 DDS/DAC frequency synthesizer, and the resultant output signal is assessed by the AD8302 gain and phase detector. This detector is capable of measuring both the gain (magnitude ratio) across the quartz crystal and the phase difference between the actuation and output signals.

Analyzing the gain curve enables the characterization of the sensor, allowing simultaneous measurement of the resonance frequency and quality factor. A key advantage of this measurement scheme is its ability to measure quartz sensor parameters in isolation, eliminating the influence of external circuitry.

TEENSY 4.0 INSIDE ITS HEART

The openQCM NEXT operates with Teensy 4.0, developed by Paul Stoffregen. This system includes an ARM CortexM7, providing CPU features to a real-time microcontroller platform. The CPU performance surpasses typical 32-bit microcontrollers, and the higher clock speed improves ADC sampling time and measurement resolution.

ACTIVE THERMAL CONTROL

The primary electronics of openQCM NEXT features an integrated, safe, and highly accurate miniaturized Peltier single-module controller: the MTD415 by Thorlabs. This compact temperature controller is optimized for high-performance thermoelectric temperature control applications. It incorporates on-chip power stage and thermal control loop circuitry, minimizing external components while maintaining efficiency.

The controller directly controls the output current, preventing current surges. An adjustable TEC current limit enhances TEC protection. Operated from a single power supply, the MTD415T provides a bipolar ±1.5 A output by linking the TEC to the output of a bipolar power stage. This true bipolar operation ensures temperature control without “dead zones” or low TEC current value nonlinearities. These TEC controllers support up to 6 W power and a maximum TEC current of ±1.5 A.

The TEC controller is compatible with a 10 kΩ thermistor, which is integrated into the Fluidic Module of openQCM NEXT.

openQCM – Powered by Novaetech S.r.l

COOKIES & PRIVACY POLICY

openQCM by https://openqcm.com is licensesd under a Creative Commons

Attribution-Non Commercial-ShareAlike 4.0 International License.