DAC1208D650 Datasheet, PDF (1/98 Pages) NXP Semiconductors – Dual 12-bit DAC; up to 650 Msps; 2×, 4× or 8× interpolating with JESD204A interface

DAC1208D650
Dual 12-bit DAC; up to 650 Msps; 2×, 4× or 8× interpolating
with JESD204A interface
Rev. 2 — 14 December 2010
Product data sheet
1. General description
The DAC1208D650 is a high-speed 12-bit dual channel Digital-to-Analog Converter
(DAC) with selectable 2×, 4× or 8× interpolating filters optimized for multi-carrier WCDMA
transmitters.
Because of its digital on-chip modulation, the DAC1208D650 allows the complex pattern
provided through lane 0, lane 1, lane 2 and lane 3, to be converted up from baseband to
IF. The mixing frequency is adjusted via a Serial Peripheral Interface (SPI) with a 32-bit
Numerically Controlled Oscillator (NCO) and the phase is controlled by a 16-bit register.
The DAC1208D650 also includes a 2×, 4× or 8× clock multiplier which provides the
appropriate internal clocks and an internal regulation to adjust the output full-scale
current.
The input data format is serial according to JESD204A specification. This new interface
has numerous advantages over the traditional parallel one: easy PCB layout, lower
radiated noise, lower pin count, self-synchronous link, skew compensation. The maximum
number of lanes of the DAC1208D650 is 4 and its maximum serial data rate is
3.125 Gbps.
The Multiple Device Synchronization (MDS) guarantees maximum skew of one output
clock period between several DAC devices. MDS incorporates modes: Master/slave and
All slave mode.
2. Features and benefits
„ Dual 12-bit resolution
„ 650 Msps maximum update rate
„ Selectable 2×, 4× or 8× interpolation
filters
„ Input data rate up to 312.5 Msps
„ Very low-noise cap-free integrated PLL
„ 32-bit programmable NCO frequency
„ Four JESD204A serial input lanes
„ 1.8 V and 3.3 V power supplies
„ LVDS compatible clock inputs
„ IMD3: 80 dBc; f_s = 640 Msps;
f_o = 140 MHz
„ ACPR: 71 dBc; two carriers WCDMA;
f_s = 640 Msps; f_o = 133 MHz
„ Typical 1.22 W power dissipation at 4×
interpolation, PLL off and 640 Msps
„ Power-down mode and Sleep modes
„ Differential scalable output current from
1.6 mA to 22 mA
„ On-chip 1.25 V reference
„ External analog offset control
(10-bit auxiliary DACs)
„ Internal digital offset control
„ Inverse (sin x) / x function