Välkommen till PCB Electronics Supply Chain +852-55175442

AD9957 1 GSPS Quadrature Digital Upconverter with 18-Bit I/Q Data Path and 14-Bit DAC

07/01/2022

Product Details

The AD9957 functions as a universal I/Q modulator and agile upconverter for communications systems where cost, size, power consumption, and dynamic performance are critical. The AD9957 integrates a high speed, direct digital synthesizer (DDS), a high performance, high speed, 14-bit digital-to-analog converter (DAC), clock multiplier circuitry, digital filters, and other DSP functions onto a single chip. It provides baseband upconversion for data transmission in a wired or wireless communications system.

The AD9957 is the third offering in a family of quadrature digital upconverters (QDUCs) that includes the AD9857 and AD9856. It offers performance gains in operating speed, power consumption, and spectral performance. Unlike its predecessors, it supports a 16-bit serial input mode for I/Q baseband data. The device can alternatively be programmed to operate either as a single tone, sinusoidal source or as an interpolating DAC.

The reference clock input circuitry includes a crystal oscillator, a high speed, divide-by-two input, and a low noise PLL for multiplication of the reference clock frequency.

The user interface to the control functions includes a serial port easily configured to interface to the SPORT of the Blackfin® DSP and profile pins to enable fast and easy shift keying of any signal parameter (phase, frequency, or amplitude).

Applications

  • HFC data, telephony, and video modems
  • Wireless base station transmissions
  • Broadband communications transmissions
  • Internet telephony

Features and Benefits

  • 1 GSPS internal clock speed (up to 400 MHz analog output)
  • Integrated 1 GSPS 14-bit DAC
  • 250 MSPS input data rate
  • Phase noise ≤ −125 dBc/Hz (400 MHz carrier @ 1 kHz offset)
  • Excellent dynamic performance >80 dB narrow-band SFDR
  • 8 programmable profiles for shift keying
  • Sin(x)/(x) correction (inverse sinc filter)
  • Reference clock multiplier
  • Internal oscillator for a single crystal operation
  • Software and hardware controlled power-down
  • Integrated RAM
  • Phase modulation capability
  • Multichip synchronization
  • Easy interface to Blackfin SPORT
  • Interpolation factors from 4× to 252×
  • Interpolation DAC mode
  • Gain control DAC
  • Internal divider allows references up to 2 GHz
  • 1.8 V and 3.3 V power supplies
  • 100-lead TQFP_EP package