ADC124S021CIMM/NOPB National Semiconductor, ADC124S021CIMM/NOPB Datasheet - Page 18

• Manufacturer Part Number: ADC124S021CIMM/NOPB
• Description: IC ADC 12BIT 4CH 200KSPS 10MSOP
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of ADC124S021CIMM/NOPB

• Number Of Bits: 12
• Sampling Rate (per Second): 200k
• Data Interface: DSP, MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 7.9mW
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
• Number Of Elements: 1
• Resolution: 12Bit
• Architecture: SAR
• Sample Rate: 200KSPS
• Input Polarity: Unipolar
• Input Type: Voltage
• Rated Input Volt: 5.25V
• Differential Input: No
• Power Supply Requirement: Single
• Single Supply Voltage (typ): 3.3/5V
• Single Supply Voltage (min): 2.7V
• Single Supply Voltage (max): 5.25V
• Dual Supply Voltage (typ): Not RequiredV
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Power Dissipation: 11mW
• Differential Linearity Error: -0.8LSB/1.1LSB
• Integral Nonlinearity Error: -1.1LSB/0.8LSB
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 10
• Package Type: MSOP
• Input Signal Type: Single-Ended
• For Use With: ADC124S021EVAL - BOARD EVALUATION FOR ADC124S021
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ADC124S021CIMM; ADC124S021CIMMTR

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7.2 Power Supply Noise Considerations
The charging of any output load capacitance requires current
from the power supply, V
the supply to charge the output capacitance will cause voltage
variations on the supply. If these variations are large enough,
they could degrade SNR and SINAD performance of the ADC.
Furthermore, discharging the output capacitance when the
digital output goes from a logic high to a logic low will dump
current into the die substrate, which is resistive. Load dis-
charge currents will cause "ground bounce" noise in the sub-
strate that will degrade noise performance if that current is
A
. The current pulses required from
18
large enough. The larger is the output capacitance, the more
current flows through the die substrate and the greater is the
noise coupled into the analog channel, degrading noise per-
formance.
To keep noise out of the power supply, keep the output load
capacitance as small as practical. If the load capacitance is
greater than 35 pF, use a 100 Ω series resistor at the ADC
output, located as close to the ADC output pin as practical.
This will limit the charge and discharge current of the output
capacitance and improve noise performance.