MAX1414CAI+ Maxim Integrated Products, MAX1414CAI+ Datasheet - Page 44

• Manufacturer Part Number: MAX1414CAI+
• Description: IC DAS 16BIT LP 28-SSOP
• Manufacturer: Maxim Integrated Products
• Type: Data Acquisition System (DAS)r

Specifications of MAX1414CAI+

• Resolution (bits): 16 b
• Sampling Rate (per Second): 60
• Data Interface: Serial
• Voltage Supply Source: Analog and Digital
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 28-SSOP
• Number Of Converters: 1
• Resolution: 16 bit
• Interface Type: Serial (4-Wire, SPI, QSPI, Microwire)
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 2.7 V
• Maximum Power Dissipation: 762 mW
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Low-Power, 16-Bit Multichannel DAS with
Internal Reference,10-Bit DACs, and RTC
Figure 27. Thermistor Application Circuit
Figure 28. Thermocouple Application Circuit
maintain the reference electrode bias voltage by virtue of
the feedback path through the sensor.
Figure 26 illustrates the MAX1407/MAX1414 in an optical
reflectometry application. The first DAC is used with an
external transistor to set the bias current through the LED
and the second DAC is used to properly bias and convert
the photodiode current to a voltage measured by the
ADC. The low input bias current into the DAC feedback
pin (FB2) allows the measurement of very small currents.
The DACs provide the flexibility in setting an accurate
and stable LED current and adjusting the bias across the
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THERMOCOUPLE
JUNCTION
R
R
Optical Reflectometry
4.7µF
CJC
REF
R
C
C
L
R
T
REF
DRDY NOT AVAILABLE ON THE MAX1409
IN0
IN1
IN2
AGND
IN0
AGND
BUF
MUX
MUX
8:1
8:1
MAX1407
MAX1408
MAX1409
MAX1414
MUX
MUX
8:1
8:1
BAND
GAP
WAKE-UP
16b ADC
MAX1407
MAX1408
MAX1414
WAKE-UP
CMP
16b ADC
CMP
REF
REF
photodiode. Set the LED bias current externally if the
MAX1409 is used in this application.
A thermistor connected in a half-bridge configuration
as shown in Figure 27 is used to measure temperatures
very accurately with the MAX1407/MAX1408/
MAX1409/MAX1414. The internal reference drives the
thermistor as well as the ADC, so the reference varia-
tion is cancelled out when calculating the temperature.
The only significant errors are from the R
the thermistor itself. The ADC performs a unipolar con-
version with the PGA set to a gain of 1V/V.
BAND
GAP
GENERATOR
INTERRUPT
GENERATOR
INTERRUPT
BUF
DRDY
INT
DRDY
INT
4.7µF
REF
Thermistor Measurement
L
resistor and