| Title |
A Sensorless and Versatile Temperature-Control System for MEMS Microheaters |
| Authors |
Bae, Byung-Hoon(Bae, Byung-Hoon) ; Yeon, Jung-Hoon(Yeon, Jung-Hoon) ; Flachsbart Bruce R.(Flachsbart Bruce R.) ; Shannon Mark A.(Shannon Mark A.) |
| Keywords |
Temperature Control System ; Microheater ; Preconcentrator ; PCR chip |
| Abstract |
In this paper, we present a temperature-controlled system for MEMS electrical resistance heaters without a temperature sensor. To rapidly control the heater temperature, the microheater system developed consists of a power supply, power amplifier, digital { underline{P}}roportional-{ underline{I}}ntegral-{ underline{D}}ifferential (PID) controller, and a quarter bridge circuit with the microheater and three resistors are nominally balanced. The microheaters are calibrated inside a convection oven to obtain the temperature coefficient with a linear or quadratic fit. A voltage amplifier applies the supply voltage proportional to the control signal from the PID controller. Small changes in heater resistance generate a finite voltage across the quarter bridge circuit, which is fed back to the PID controller to compare with the set-point and to generate the control signal. Two MEMS microheaters are used for evaluating the developed control system - a NiCr serpentine microheater for a preconcentrator and a Nickel microheater for { underline{P}}olymerase { underline{C}}hain { underline{R}}eaction (PCR) chip. |