1. CST employees 5,500
EUR 750 million
A Combined Pressure and Temperature Sensor without external temperature probe

2. Content (1) Key P/T Sensor Specifications
(2) Patented Thin Film Technology
(3) Sensor Design for CO2 / R744 MACS
(4) Finite Element Modeling / Simulation
(5) Qualification Testing
(6) Other Thin Film Applications and Sensor products

3. (1) Key P/T Sensor Specifications
Pressure: Measurement Range 0 to 170 Bar Accuracy < ± 1,0% (F.Sp.) Response time ~4 ms (t63)
Temperature: Media °C to +180°C Accuracy ~ ± 3 K Response time < 10 sec (t63) Ambient Temperature up to 135°C
Electrical Interface: 3-pin LIN2.0, 3-pin PWM, pin P/T analog

4. (2) Patented Thin Film Technology
Thin Film Element on SST
Sputtered Metal Strain Gauge
TiON Strain Gauge with high K-Factor/ Gauge Factor: K: TiON ~ 5 (CrNi ~ 1,1..2) K-Factor: dR/R= K * dl/l
High Temperature Resistance (330°C)
Pressure Range: 10 to Bar
6 mm

5. (3) Sensor Design for CO2 / R744 MACS
Digital output: LIN2.0 or PWM (Temperature output embedded in signal)
Integrated Temp. feature: Less part complexity, higher reliability, less flow restriction and reduced leakage risk.
Long term stability, Rugged Design.
Smallest possible thread interface: M10x1mm

6. Exploded View / Cross Sectional
Connector
Flexwire
Component board
with µC
Housing
Combined Sensor Assembly (p,T)
DV Chip
p,T

7. Kavlico DV Chip
Dual Frequency-Output ASIC for Thin-Film and PRT Resistive type sensors:
Ratiometric multiplexed frequency (digital) output for Sensor (Pressure-) and Temperature-data.
Coarse gain and offset calibration via serial-interface, allowing wide range of sensors.
Fine calibration by µP ; calibration coefficients to be stored in memory of µP.
Extreme temperature range ( -50ºC to +200ºC ).
Low-Power (sleep mode and 3mA operational current)
Self-diagnostics and failure analysis.

8. DV Chip placement on Thin Film Flexure
Accurate Temperature measurement independent from ambient temperature.
Digital, non-susceptible output (temperature output embeded in signal).
Bridge pads
Bumps on DV Chip
Underfill Adhesive
Electrical Contact

9. Schematic p T Sensing (Sensor assy) Conditioning (PC Board) DV chip
Flexwire
Inter-connection
Micro Controller
Thin Film
Strain
Gauge
LIN2.0
Transceiver
Out

10. (4) Finite Element Modeling of P/T Sensor

11. Effect of Chip on Diaphragm Stress and Deflection
The influence of DV chip on the stress distribution and deflection of diaphragm is small
Condition: 180ºC temperature, 150 bar pressure R r

12. Thermal Analysis Impact to electrical Components (PCB)
Ambient Conditions:
25ºC still air
150ºC still air 150ºC air flow / m/s
135ºC still air
200 kg/h and 180ºC or 165ºC

13. Temperature Distributions after 5 Min. (25ºC Ambient Temperature)
25°C, Voo = 0m/s
Printed Circuit Board
112~140ºC
Initial Fluid Temperature: 25ºC; Transient to 180ºC

14. b) Temperature Distributions after 5 Min. (150ºC Ambient Temperature)
150°C, Voo = 0m/s
150°C, Voo = 4.4m/s
167~173ºC
166~172ºC
Printed Circuit Board
Initial Fluid Temperature: 25ºC; Transient to 180ºC

15. Replace PCB
ULTEM 2310 Polyetherimide Plastic Connector
Circuit Board
Stainless Steel 304L
Mount the circuit board to components with low thermal conductivity (plastics) away from the metal housing.

16. c) Design at 135ºC Ambient Temperature
CO2 Temperature
Printed Circuit Board Temperature ºC
5 min of 180ºC
5 min of 165ºC ºC
Initial Fluid Temperature: 135ºC; Transient to 180ºC and 165ºC

17. Conclusions
DV chip has negligible influence on the performance of sensor diaphragm / pressure sensor functionality.
By connecting the circuit board to plastics and away from the metal housing, the circuit board temperature can be reduced to around
~ 140ºC under 135ºC ambient Temperature

18. (5) Qualification Testing
Leackage test Requirement <1,0 gram per year The test is carried out at an external test lab, specialized on these kind of tests.
Design validation test on sensor level Start after sample build in July Duration appr. 6 month.

19. (6) Other Thin Film Application and Sensor Products:
Direct Fuel Injection / Common Rail
In-Cylinder Pressure
Transmission / Break Pressure
Compressed Natural Gas (CNG)
Traction Control
(Mobile) Hydraulic Pressure / Controls
HVAC / Hydraulic Machinery

20. Contact: Mr. Markus Butenop Director of Sales KAVLICO GmbH Potsdamer Str Minden Germany Phone: +49 (0) – 171 Fax.: +49 (0) – Web: /