aduc7032 Analog Devices, Inc., aduc7032 Datasheet - Page 21

• Manufacturer Part Number: aduc7032
• Description: Microconverter Integrated, Precision Battery Sensor
• Manufacturer: Analog Devices, Inc.

Preliminary Technical Data
SPECIFICATION TERMINOLOGY
CONVERSION RATE:
The conversion rate specifies the rate at which an output result
is available from the ADC, once the ADC has settled.
The sigma-delta conversion techniques used on this part mean
that while the ADC front-end signal is over-sampled at a
relatively high sample rate, a subsequent digital filter is
employed to decimate the output to give a valid 16-Bit data
conversion result at output rates from 1Hz to 8 KHz.
It should also be noted that when software switches from one
input to another (on the same ADC), the digital filter must first
be cleared and then allowed to average a new result. Depending
on the configuration of the ADC and the type of filter this can
take multiple conversion cycles.
INTEGRAL NON_LINEARITY (INL):
This is the maximum deviation of any code from a straight line
passing through the endpoints of the transfer function. The
endpoints of the transfer function are zero scale, a point 0.5
LSB below the first code transition and full scale, a point 0.5
LSB above the last code transition (111 . . . 110 to 111 . . . 111).
The error is expressed as a percentage of full scale.
NO MISSING CODES:
This is a measure of the Differential Non-Linearity of the ADC.
The error is expressed in bits and specifies the number of codes
(ADC results) as 2^N Bits, where is N = No Missing Codes,
guaranteed to occur through the full ADC input range.
Acronyms used in this Datasheet:
ADC
ARM
JTAG
LIN
LSB
LVF
MCU
MMR
MSB
PID
POR
PSM
RMS
Analog to Digital Converter
Advanced RISC Machine
Joint Test Action Group
Local Interconnect Network
Least Significant Byte/Bit
Low Voltage Flag
MicroController
Memory Mapped Register
Most Significant Byte/Bit
Protected Identifier
Power On Reset
Power Supply Monitor
Root Mean Square
Rev. PrD | Page 21 of 128
OFFSET ERROR:
This is the deviation of the first code transition ADC input
voltage from the ideal first code transition.
OFFSET ERROR DRIFT:
Offset Error Drift is the variation in absolute offset error with
respect to temperature. This error is expressed as LSBs per °C.
GAIN ERROR
This is a measure of the span error of the ADC. It is a measure
of the difference between the measured and the ideal span
between any two points in the transfer function.
OUTPUT NOISE:
The output noise is specified as the standard deviation (or 1 X
Sigma) of ADC output codes distribution collected when the
ADC input voltage is at a dc voltage. It is expressed as µ rms.
The output or RMS noise can be used to calculate the Effective
Resolution of the ADC as defined by the following equation
Effective Resolution= Log
The peak-to-peak noise is defined as the deviation of codes that
fall within 6.6 X Sigma of the distribution of ADC output codes
collected when the ADC input voltage is at dc. The peak-to-
peak noise is therefore calculated as 6.6 times the RMS noise.
The peak-to-peak noise can be used to calculate the ADC
(Noise Free, Code) Resolution for which there will be no code
flicker within a 6.6-Sigma limit as defined by the following
equation
Noise Free Code Resolution = Log
Peak Noise) Bits
2
(Full-Scale Range / RMS Noise) Bits
2
(Full-Scale Range / Peak to
ADuC7032