IC-HO Datasheet, PDF (1/2 Pages) IC-Haus GmbH – GENERAL PURPOSE SENSOR INTERFACE

iC-HO
GENERAL PURPOSE SENSOR INTERFACE
iC-HO suits for various applications: mass flow metering, gas
sensing and pressure sensing. Besides the IC only a few exter-
nal components are required: a cost effective microcontroller
and/or an EEPROM, and the sensor itself. iC-HO is completely
controllable and monitorable by the microcontroller via SPI.
Alternatively, stand-alone applications can boot from the CRC-
secured external SPI EEPROM.
Instrumentation PGA inputs allow gain and offset calibration,
and temperature stabilization. An integrated look-up table (LUT)
featuring 9 breakpoints can be used to correct nonlinear sensor
characterstics directly within the sensor interface IC.
A digital PI-controller is available to drive a wide range of
MEMS heater resistors with up to 115 mW in an absolute or
relative temperature range from -25 °C to + 660 °C. A fixed set
point or sequence controller mode can be selected.
Matching constant current sources are available to bias up to
three sensor resistors. The analog ratiometric differential output
signal is implemented with a 10-bit D/A converter.
Applications
• Flow Sensors
• Pressure Sensors
• Gas Sensors
Features
• Ultra-low offset and low-noise PGA inputs
• 11-bit analog to digital conversion
• Signal offset correction
• Configurable temperature drift compensation
• Linearization of sensor characteristic by look-up table
• Measurement data output digital and analog (10-bit D/A)
• Differential output of ratiometric voltage
• Adjustable PI heater control
• Signal and system monitoring functions
• Fault indication at open-drain error output
• Sensor resistor bias by adjustable current sources
• Integrated 8-bit temperature sensing
• SPI-master (for EEPROM) and SPI-slave interfaces for
device configuration and controller operation
• 5 V supply voltage
• Operating temperature range of -20 °C to 105 °C
VDDAS
SUS3
SUS2
SUS1
GNDAS
Configurable Sensor
Supply
VDDA VREF
VAMP
Bandgap
Reference
Osillator
Error Monitor
PGA Input
SPIN
+
A
SNIN
-
D
RBP
RBN
HEATP
HEATN
IHEAT
GNDHS
iC-HO
Heater Control
A
D
PI
A
D
D
A
Look Up Table
Analog Output
A
+
D^-
RAM
Main Control
Chip Temp.
Power-Down
Reset
GNDA
I/O Interface
SPI Slave
EEPROM
Interface
SPI Master
VDD
NERR
OUTP
OUTN
NCS_S
SCK_S
MOSI_S
MISO_S
NCS_M
SCK_M
MOSI_M
MISO_M
GND
Am Kuemmerling 18 • D-55294 Bodenheim, Germany
Tel. [phone] • Fax [phone] • http://www.ichaus.com