NAU7802QGI

Part: NAU7802 — Nuvoton

Type: Precision Low-Power 24-bit Analog-to-Digital Converter (ADC)

Description: A precision low-power 24-bit analog-to-digital converter with an onboard low-noise programmable gain amplifier (PGA), onboard RC or Crystal oscillator, and a precision 24-bit sigma-delta ADC, capable of up to 23-bit ENOB performance.

Operating Conditions:

• Supply voltage: 2.7–5.5 V (DVDD, AVDD)
• Operating temperature: -40 to +85 °C
• PGA gain range: 1 to 128
• External differential reference voltage range: 0.1–5 V

Absolute Maximum Ratings:

• Max supply voltage: +6.0 V (DVDD, AVDD)
• Max storage temperature: +150 °C

Key Specs:

• Resolution: 24 bits (No missing codes)
• Effective Number of Bits (ENOB): Up to 23 bits
• RMS Noise: 50 nV (10 SPS, PGA gain = 128)
• Integral nonlinearity: ±0.0015 % of FS (With calibration)
• Offset error: +/-0.3 ppm of FS (With calibration, 1024 samples)
• Gain error: 0.01 % (With calibration)
• Power Down Current: 0.2 μA (typ) to 1 μA (max)
• Common-mode rejection: 100 dB (at DC 2.5 V ± 0.5 V)

Features:

• On-chip AVDD regulator (programmable 2.4V ~ 4.5V)
• Simultaneous 50Hz and 60Hz rejection (-90dB)
• Programmable ADC data output rates
• External crystal oscillator or on-chip RC oscillator (4.9152MHz)
• On-chip calibration
• On-chip power-on reset circuit
• On-chip temperature sensor
• Low Power Consumption and Programmable Power Management Options
• 2-wire interface compatible with I2C protocol

Applications:

• Weigh scales
• Strain Gauge
• Industrial process control
• Liquid/gas flow control
• Pressure sensors
• Voltage monitors

Package:

• SOP-16 (150mil)
• PDIP-16 (300mil)
• QFN-16

• Supply Voltage: 2.7V~5.5V
• On-chip AVDD regulator for internal analog circuit or external load cell
• o Programmable AVDD: Off, 2.4V ~ 4.5V with eight options
• Minimum 10mA AVDD LDO output drive capability at 3.0V output voltage* 1
• 23-bit effective precision analog-to-digital converter
• Simultaneous 50Hz and 60Hz rejection (reaching - 90dB )
• RMS Noise:
• o 50nV in 10 SPS data output rate and PGA gain = 128
• o 150nV in 80 SPS data output rate and PGA gain = 128
• Programmable PGA gains from 1 to 128
• Programmable ADC data output rates
• External differential reference voltage ranges from 0.1V ~ 5V
• System clock: External crystal oscillator or on-chip RC oscillator (4.9152Mhz)
• On-chip calibration
• On-chip power-on reset circuit
• On-chip temperature sensor
• Low Power Consumption and Programmable Power Management Options
• o < 1μA standby current
• External 4.9152MHz Crystal oscillator
• System clock:
• o Internal 4.9152MHz RC oscillator (power-on default system clock)
• o External 4.9152MHz Crystal oscillator
• MCU control interface: 2-wire interface compatible with I2C protocol
• Operating Temperature: -40~85 °C
• Packages:
• o SOP-16 (150mil) / PDIP-16 (300mil) / QFN-16
• o Package is Halogen-free, RoHS-compliant and TSCA-compliant

• Weigh scales
• Strain Gauge
• Industrial process control
• Liquid/gas flow control
• Pressure sensors
• Voltage monitors

1 Note:

The LDO load current at AVDD should not exceed 10mA. DVDD must be 0.3V greater than desired AVDD output voltage.

Note: QFN device center pad underneath should be connected to AVSS.

(Unless otherwise specified; Typical value is tested at TA=25 ° C, DVDD = 5V, AVDD = 5V)

Note : Exposure to conditions beyond those listed under absolute maximum ratings may adversely affects the life time and reliability

• AVDD should not exceed DVDD supply voltage

This section includes both circuit diagram information and recommendations for programming the device. Programming is essential, as the device will not function until various default settings are changed to values appropriate for the application.