HI5805BIB Просмотр технического описания (PDF) - Renesas Electronics

Номер в каталоге

Компоненты Описание

производитель

HI5805BIB

12-Bit, 5MSPS A/D Converter

Renesas Electronics 

HI5805

Dynamic Performance Definitions

Fast Fourier Transform (FFT) techniques are used to evaluate

the dynamic performance of the HI5805. A low distortion sine

wave is applied to the input, it is coherently sampled, and the

output is stored in RAM. The data is then transformed into the

frequency domain with an FFT and analyzed to evaluate the

dynamic performance of the A/D. The sine wave input to the

part is -0.5dB down from full scale for all these tests. SNR and

SINAD are quoted in dB. The distortion numbers are quoted in

dBc (decibels with respect to carrier) and DO NOT include any

correction factors for normalizing to full scale.

Signal-to-Noise Ratio (SNR)

SNR is the measured RMS signal to RMS noise at a specified

input and sampling frequency. The noise is the RMS sum of all

of the spectral components except the fundamental and the

first five harmonics.

Signal-to-Noise + Distortion Ratio (SINAD)

SINAD is the measured RMS signal to RMS sum of all other

spectral components below the Nyquist frequency, fS/2,

excluding DC.

Effective Number Of Bits (ENOB)

The effective number of bits (ENOB) is calculated from the

SINAD data by:

ENOB = SINAD + VCORR-1.76/6.02,

where: VCORR = 0.5dB.

VCORR adjusts the ENOB for the amount the input is below

fullscale.

Total Harmonic Distortion (THD)

THD is the ratio of the RMS sum of the first 5 harmonic

components to the RMS value of the fundamental input signal.

2nd and 3rd Harmonic Distortion

This is the ratio of the RMS value of the applicable harmonic

component to the RMS value of the fundamental input signal.

Spurious Free Dynamic Range (SFDR)

SFDR is the ratio of the fundamental RMS amplitude to the

RMS amplitude of the next largest spur or spectral

component in the spectrum below fS/2.

Intermodulation Distortion (IMD)

Nonlinearities in the signal path will tend to generate

intermodulation products when two tones, f1 and f2, are

present at the inputs. The ratio of the measured signal to the

distortion terms is calculated. The terms included in the

calculation are (f1 + f2), (f1 - f2), (2f1), (2f2), (2f1 + f2),

(2f1 - f2), (f1 + 2f2), (f1 - 2f2). The ADC is tested with each

tone 6dB below full scale.

FN3984 Rev 7.00

March 31, 2005

Page 11 of 12

Share Link: