ZSSC3122 Datasheet, PDF (1/64 Pages) List of Unclassifed Manufacturers – Low Voltage Capacitive Sensor Signal Conditioner

cLite^TM Low-Voltage Capacitive
Sensor Signal Conditioner
ZSSC3122
Datasheet
Brief Description
The ZSSC3122 is a CMOS integrated circuit for
accurate capacitance-to-digital conversion and
sensor-specific correction of capacitive sensor sig-
nals. Digital compensation of sensor offset, sensiti-
vity, and temperature drift is accomplished via an
internal digital signal processor running a correction
algorithm with calibration coefficients stored in a
non-volatile EEPROM.
The ZSSC3122 is configurable for capacitive sen-
sors with capacitances up to 10pF and a sensitivity
of 125aF/LSB. It is compatible with both single
capacitive sensors (both terminals must be
accessible) and differential capacitive sensors.
Measured and corrected sensor values can be
output as I²C™ ^*, SPI, PDM, or alarms.
The I²C™ interface can be used for a simple PC-
controlled calibration procedure to program a set of
calibration coefficients into an on-chip EEPROM.
The calibrated ZSSC3122 and a specific sensor are
mated digitally: fast, precise, and without the cost
overhead of trimming by external devices or laser.
Features
• Maximum target input capacitance: 10pF
• Sampling rates as fast as 0.7ms at 8-bit resolution;
1.6ms at 10-bit; 5.0ms at 12-bit; 18.5ms at14-bit
• Digital compensation of sensor: piece-wise 1^st
and 2^nd order sensor compensation or up to
3^rd order single-region sensor compensation
• Digital compensation of 1^st and 2^nd order
temperature gain and offset drift
• Internal temperature compensation reference
(no external components)
• Programmable capacitance span and offset
• Layout customized for die-die bonding with sensor
for low-cost, high-density chip-on-board assembly
• Accuracy ^† as high as
±0.25% FSO@ -20 to 125°C, 3V, 5V, Vsupply ±10%
Benefits
• Minimized calibration costs: no laser trimming,
one-pass calibration using a digital interface
• Excellent for low-power battery applications
Interfaces
• I²C™ or SPI interface—easy connection to a
microcontroller
• PDM outputs (Filtered Analog Ratiometric) for
both capacitance and temperature
• Up to two alarms that can act as full push-pull or
open-drain switches
Physical Characteristics
• Supply voltage: 1.8 to 5.5V
• Typical current consumption 650μA down to
60μA depending on configuration
• Typical Sleep Mode current: ≤ 1μA at 85°C
• Operation temperature: –20°C to +125°C
• Die or TSSOP14 package
Available Support
• ZSSC3122 SSC Evaluation Kit available: SSC
Evaluation Board, samples, software,
documentation.
• Support for industrial mass calibration available.
• Quick circuit customization option for large
production volumes.
Application: Digital Output, Alarms
VSUPPLY
(+1.8V to 5.5V)
0.1µF
0.1µF
GND
VDD
Vcore
VSS
C0
CC
cLite^™
ZSSC3122
Ready
SDA/MISO
SCL/SCLK
SS
Alarm_High
Alarm_Low
* _I2_{C™ is a registered trademark of NXP.}
† _{See data sheet section 1.3 for restrictions.}
© 2016 Integrated Device Technology, Inc.
1
January 25, 2016