DC890B Analog Devices

DEMO MANUAL DC890B DC890B QuickStart Guide DESCRIPTION Demonstration circuit DC890B along with PScope soft- various analyses on the data including calculating SNR, ware provides a USB based Windows PC hosted digital SINAD, THD, SFDR and ENOB. The digitized input, an FFT data acquisition system supporting CMOS/LVDS output of the collected data, the primitive wave of the sample set ADCs up to 250Msps. The DC890B must be powered from or an IFFT of modified frequency domain data is plotted to an external 6VDC 0.5VDC power supply when operat- a display window to facilitate analyzing distortion products ing in LVDS mode. When operating in CMOS mode, the and sources. Figure 1 shows a picture of the DC890B. The external power supply is optional. The Linear Technology DC890B is connected to the ADC demonstration circuit via supplied PScope evaluation software automatically detects a 100-pin edge connector, to the PC by a USB A-B cable and the DC890B and can also detect many of the standard to an optional power supply either by a 5mm power plug ADC demonstration circuits boards. The DC890B will or optionally by turrets. Figure 2 details the connections. not enable LVDS mode unless an external 6.0VDC power Design files for this circuit board are available at source is available. This system provides for fast and easy DEMO MANUAL DC890B OPERATING PRINCIPLES The DC890B is capable of collecting a block of data samples Refer to the PScope software help for information on the from an ADC demonstration circuit initiated either by an various operating modes and options. The conversion internally generated trigger or an externally supplied 2.5V clock to the DC890B is supplied via the ADC demonstra- CMOS level trigger of user selected edge. The external tion circuit either from an optional on board oscillator if trigger is TTL or CMOS compatible (the trigger line is installed or an external signal generator connected to the diode clamped to the 2.5V Rail through a 475 resistor). ADC demonstration circuit. QUICK START PROCEDURE To prevent damage to the DC890B, it is important to follow circuit being evaluated. Please refer to it for proper the equipment setup procedure outlined below: jumper settings, input power requirements and input signal levels and frequency ranges. 1. Do not plug the DC890B into the PC USB port before running the installation program 7. Apply an appropriate conversion clock and analog input signal to the ADC demonstration board. 2. Download the PScope installation program from