3-198
HSP50016
Digital Down Converter
The Digital Down Converter (DDC) is a single chip
synthesizer, quadrature mixer and lowpass filter. Its input
data is a sampled data stream of up to 16 bits in width and
up to a 75 MSPS data rate. The DDC performs down
conversion, narrowband low pass filtering and decimation to
produce a baseband signal.
The internal synthesizer can produce a variety of signal
formats. They are: CW, frequency hopped, linear FM up
chirp, and linear FM down chirp. The complex result of the
modulation process is lowpass filtered and decimated with
identical real filters in the in-phase (I) and quadrature (Q)
processing chains.
Lowpass filtering is accomplished via a High Decimation
Filter (HDF) followed by a fixed Finite Impulse Response
(FIR) filter. The combined response of the two stage filter
results in a -3dB to -102dB shape factor of better than 1.5.
The stopband attenuation is greater than 106dB. The
composite passband ripple is less than 0.04dB. The
synthesizer and mixer can be bypassed so that the chip
operates as a single narrow band low pass filter.
The chip receives forty bit serial commands as a control
input. This interface is compatible with the serial I/O port
available on most microprocessors.
The output data can be configured in fixed point or single
precision floating point. The fixed point formats are 16,
24, 32, or 38-bit, two’s complement, signed magnitude, or
offset binary.
The circuit provides an IEEE 1149.1 Test Access Port.
Features
75 MSPS Input Data Rate
16-Bit Data Input; Offset Binary or 2’s Complement
Format
Spurious Free Dynamic Range Through Modulator
>102dB
Frequency Selectivity: <0.006Hz
Identical Lowpass Filters for I and Q
Passband Ripple: <0.04dB
Stopband Attenuation: >104dB
Filter -3dB to -102dB Shape Factor: <1.5
Decimation Factors from 32 to 131,072
IEEE 1149.1 Test Access Port
HSP50016-EV Evaluation Board Available
Applications
Cellular Base Stations
Smart Antennas
Channelized Receivers
Spectrum Analysis
Related Products: HI5703, HI5746, HI5766 A/Ds
Block Diagram
Ordering Information
PART
NUMBER
TEMP.RANGE
(
o
C)
PACKAGE
PKG.
NO.
HSP50016JC-52
0 to 70
44 Ld PLCC
N44.65
HSP50016JC-75
0 to 70
44 Ld PLCC
N44.65
HSP50016GC-52
0 to 70
48 Ld CPGA
G48.A
COMPLEX
SINUSOID
GENERATOR
DATA
16
HIGH DECIMATION
FILTER
HIGH DECIMATION
FILTER
LOW PASS FIR
FILTER
LOW PASS FIR
FILTER
COS
SIN
I
Q
CONTROL
TEST ACCESS
PORT/CTRL
O
F
OUTPUT
I
Q
CLK
TEST ACCESS
PORT
CLK
CLK
R
CLK
4R
OR
CLK
2R
CLK
SER
IQSTRB
IQCLK
Data Sheet
February 1999
File Number
3288.6
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
http://www.intersil.com or 407-727-9207
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Copyright
Intersil Corporation 1999