National Semiconductor's New 12-Bit ADCs for WiMAX Provide the Industry's Highest SFDR of 84.1 dB at 250 MHz Input Frequency. Available in dual data rate, low-voltage differential signaling (LVDS) and CMOS output options, the ADCs are targeted at demanding WiMAX and 3G wireless communications applications. In high intermediate frequency (IF) sampling receiver applications, the 1.1 GHz bandwidth capability of these ADCs provides high spurious free dynamic range (SFDR) and signal-to-noise ratio (SNR) performance that extends well beyond 250 MHz input frequencies. This enables the system designer to digitize the signal at the first IF, thereby eliminating a down conversion stage, which reduces component count and system power.
The 12-bit ADC12C170 with parallel CMOS outputs and 12-bit ADC12V170 with dual data rate, parallel LVDS outputs offer the industry's highest SFDR above 250 MHz input frequencies. Compared to competitive devices, the ADC12C170 at 84.1 dB offers 5.5 dB better SFDR and the ADC12V170 at 83 dB offers 3.8 dB better SFDR at an input frequency of 250 MHz.
At 1.1 GHz, the ADC14V155 delivers 57 percent higher full-power bandwidth than competing 14-bit ADCs. The device also provides an industry-leading SFDR of 85 dB and SNR of 69.5 dB at an input frequency of 238 MHz. The ADC14V155, with dual data rate, parallel LVDS outputs is the latest addition to National's high-speed 14-bit ADC family, joining the ADC14155, with CMOS outputs, introduced in mid-2006.
These ADCs are well-matched to work with National's high-speed op amps and highly-integrated clock conditioners, such as the single-chip LMK03000, to provide a complete signal-path system solution.
