TL/H/11454
ADC16071/ADC16471
16-Bit
Delta-Sigma
192
ks/s
Analog-to-Digital
Converters
February 1995
ADC16071/ADC16471
16-Bit Delta-Sigma 192 ks/s Analog-to-Digital Converters
General Description
The ADC16071/ADC16471 are 16-bit delta-sigma analog-
to-digital converters using 64 c oversampling at
12.288 MHz. A 5th-order comb filter and a 246 tap FIR deci-
mation filter are used to achieve an output data rate of up to
192 kHz. The combination of oversampling and internal digi-
tal filtering greatly reduces the external anti-alias filter re-
quirements to a simple RC low pass filter. The FIR filters
offer linear phase response, 0.005 dB passband ripple, and
t
90 dB stopband rejection. The ADC16071/ADC16471’s
analog fourth-order modulator uses switched capacitor
technology. A built-in fully-differential bandgap voltage ref-
erence is also included in the ADC16471. The ADC16071
has no internal reference and requires externally applied
reference voltages.
The ADC16071/ADC16471 use an advanced BiCMOS pro-
cess for a low power consumption of 500 mW (max) while
operating from a single 5V supply. A power-down mode re-
duces the power supply current from 100 mA (max) in the
active mode to 1.3 mA (max).
The ADC16071/ADC16471 are ideal analog-to-digital front
ends for signal processing applications. They provide a
complete high resolution signal acquisition system that re-
quires a minimal external anti-aliasing filter, reference, or
interface logic.
The ADC16071/ADC16471’s serial interface is compatible
with the DSP56001, TMS320, and ADSP2100 digital signal
processors.
Key Specifications
Y
Resolution 16 bits
Y
Total harmonic distortion
48 kHz output data rate b94 dB (typ)
192 kHz output data rate b80 dB (typ)
Y
Maximum output data rate 192 kHz (min)
Y
Power dissipation
— Active
192 kHz output data rate 500 mW (max)
48 kHz output data rate 275 mW (max)
— Power-down 6.5 mW (max)
Key Features
Y
Voltage reference (ADC16471 only)
Y
Fourth-order modulator
Y
64 c oversampling with a 12.288 MHz sample rate
Y
Adjustable output data rate from 7 kHz to 192 kHz
Y
Linear-phase digital anti-aliasing filter:
— 0.005 dB passband ripple
— 90 dB stopband rejection
Y
Single a5V supply
Y
Power-down mode
Y
Serial data interface compatible with popular
DSP devices
Applications
Y
Medical instrumentation
Y
Process control systems
Y
Test equipment
Y
High sample-rate audio
Y
Digital Signal Processing (DSP) analog front-end
Y
Vibration and noise analysis
Connection Diagram
TL/H/11454–2
Ordering Information
Part No. Package
NS Package
No.
ADC16471CIN 24-Pin Molded DIP N24C
ADC16471CIWM 24-Pin SOIC M24B
ADC16071CIN 24-Pin Molded DIP N24C
ADC16071CIWM 24-Pin SOIC M24B
TRI-STATE is a registered trademark of National Semiconductor Corporation.
C
1995 National Semiconductor Corporation RRD-B30M75/Printed in U. S. A.