DC1959B is a low noise and spurious fractional-N synthesizer with integrated VCO produced by Linear Technology Corporation.
This manual provides setup instructions and configuration details for the DC1959B demonstration circuit, which features the LTC6948 ultralow noise and spurious fractional-N synthesizer with integrated VCO. It includes quick start procedures, component layouts, parts lists, and troubleshooting guidance for evaluating the synthesizer's performance.
The DC1959B comes in four versions (A, B, C, D) corresponding to different LTC6948 variants and frequency ranges. It uses a DC590 USB controller and FracNWizard software for SPI communication and frequency planning. The board includes SMA connectors for reference input and differential RF output, banana jack power inputs, and jumper settings for mute control and voltage selection.
| VCO Frequency Range | 2.240 to 3.740 GHz (DC1959B-A) |
|---|---|
| Reference Frequency Input | 100MHz SMA |
| RF Output | 907MHz, 0dBm |
| Loop Bandwidth | Approximately 160kHz |
The FracNWizard software is required to communicate with the LTC6948 synthesizer via the DC590 USB controller.
Set jumper JP1 to the GND position to mute the RF output; set it to 3.3V to unmute.
The DC1959B requires 3.3V and 5V power supplies, with banana jack inputs for both voltages.