Oscilloscopes aid embedded designs
Rick Nelson, Chief Editor -- Test & Measurement World, 3/1/2008
“Small adjustments in microcontroller firmware can produce significant improvements in embedded-system performance,” says David Saar, president of Saar Associates, in the Webcast “Embedded design techniques for optimizing control parameters.” In the Webcast, sponsored by Tektronix in conjunction with Test & Measurement World and EDN and presented live January 23, Saar describes how to use a mixed-signal oscilloscope to select the right values for parameters such as gains, offsets, delays, hysteresis values, and pulse-width-modulation (PWM) parameters in embedded systems. In particular, Saar notes that a mixed-signal scope with deep memory can often gather necessary measurement data in a single acquisition.
 An embedded controller in an LED power system yields its operational secrets to a mixed-signal oscilloscope. |
Saar provides specific application examples, including that of a high-brightness LED power system (figure) that controls brightness by means of a microcontroller-based PWM controller. He describes how to use a mixed-signal scope to monitor the gate of the controller's power transistor as well as analog levels such as power-transistor drain voltage, LED voltage, and LED current. Saar also describes how to correlate microcontroller program execution with measured results by inserting a temporary marker in the microcontroller's software. He further describes how to use the observed data to choose an optimum hysteresis level that minimizes ripple.
Other examples presented in the Webcast include a battery-powered stepper-motor controller, for which Saar explains how to determine optimum step delays for normal operation and for operation near the end of battery life. He also presents an ultrasonic range detector, for which he shows how to determine optimum gain settings and optimum transmitter voltage and frequency.
You can view the archived Webcast to see detailed information on these three examples.
| For other T&MW Webcasts, see our Webcast page. |
