Silicon Pressure Sensor ICs KP100 Surface Mount Capacitive Silicon Absolute Pressure Sensor KP100 Data Sheet Features • • • • • • Digital output Serial Peripheral Interface (SPI) Offset calibrated CMOS compatible surface micromachining Diagnostic modes SMD housing P-DSOF-8-3 Type Marking Ordering Code Pressure Range Package KP100 see below Q62705-K348 P-DSOF-8-3 60 kPa- 130 kPa Marking Each device is marked with a human readable code on the side of Pins 5 to 8. This code contains the supplier logo, a date code, wafer lot number and an offset code. Product Description The KP100 is an absolute pressure sensor with SPI interface for side airbag applications. The basic accuracy including temperature drift is ±5%. The KP100 offers some diagnosis features in order to allow a sensor status analysis. Data Book 1 2003-05 KP100 Pin Configuration (top view) Figure 1 Pin Definitions and Functions Pad No. Symbol Function 1 CLKS Input; clock for serial interface 2 CS Input; chip select, active low 3 DTA_OUT Output of the serial interface 4 CLK_IN Input; external clock = 4/8 MHz 5 VDD 5 V power supply terminal 6 DTA_RDY Data ready signal for serial interface 7 DTA_IN Input for serial interface 8 VSS Ground potential Data Book 2 2003-05 KP100 Figure 2 Data Book Block Diagram of the KP100 3 2003-05 KP100 Functional Description The IC consists of a surface micromachined pressure sensor, a sigma-delta A/D-converter, a digital filter and the SPI-interface. In normal operation, the applied pressure has to be in the range between 60 kPa and 130 kPa and delivers output codes between typ. 7680 and typ. 20190 digits. Absolute Maximum Ratings Parameter Symbol Limit Values Unit min. typ. max. VCLK_IN ICKL_IN – 0.3 – VDD +0.3 V – 100 – 100 VCLKS VCS VDTA_IN ICLKS ICS IDTA_IN – 0.3 – VDD +0.3 V – 1.0 – 1.0 mA TS Tj – 40 – 90 °C – 40 – 100 °C pOL – – 200 kPa Clock Oscillator Voltage on pin CLK_IN Current on pin CLK_IN µA Serial Peripheral Interface (SPI) Input voltage on pins CLKS, CS and DTA_IN Current on pins CLKS, CS, DTA_IN Temperature Storage temperature Junction temperature Pressure Pressure overload Note: Stresses above those listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ESD Protection Human Body Model (HBM) tests according to: Standard EIA/JESD22-A114-B HBM (covers MIL STD 883D) Parameter ESD-Protection Data Book Symbol VESD Limit Values min. max. – ±2 4 Unit Notes kV R = 1.5 kΩ, C = 100 pF 2003-05 KP100 Operating Range Parameter Supply voltage Supply current External clock frequency CLK_IN Operating temperature range Pressure range Symbol VDD IDD fCLK_IN TA RP Limit Values Unit min. typ. max. 4.5 5.0 5.5 V 1.0 1.8 2.5 mA – 4/8 4.2/8.4 MHz – 40 – + 90 °C 60 – 130 kPa Electrical Characteristics Parameter Symbol Limit Values min. typ. max. Unit Digital output range RY 0 – 65534 digits Resolution – – 2 – digits Output range for a typ. sensitivity (value Y see below) over specified pressure range (for zero offset, at 25 °C) 7680 – 20190 digits Offset a The offset is written on the package in an LC encoded Form, called LC (calculation see below) – 3000 – 00 6984 TT digits Sensitivity (see below: transfer function) b – 46 – digits/ (kPa)1.25 Exponent of transfer function (see below) c – 1.25 – 1 Repeatability – 16 – digits Noise σ – – 14.5 digits Information rate fL f– 3 DB – 7.8 – kHz – 360 – Hz ε – ± 5% – 1 Filter cutoff frequency (– 3 dB) Accuracy over temperature range (-40 °C to 90 °C) Data Book 5 2003-05 KP100 *Calculation of the offset a from the LC-code written on the package The offset of each pressure sensor is individually measured at the Infineon production line. It is written on the sensor package in encoded Form. The so called LC code consists of two signs X and Y. The offset a is calculated from the code using the table and the formula below: a = (X × 25 + Y) × 16 – 3000 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 0 1 2 3 4 5 6 7 8 9 A V C D E F G H K L M P R S T Electrical Characteristics Parameter Symbol Limit Values Unit min. typ. max. – – 5 pF –5 – 5 µA 3.5 – – V – – 1.5 V 150 Input pin CLK_IN CCKL_IN ICKL_IN VHCKL_IN VLCKL_IN VINHYST VOH – – mV 0.8 VDD – – V “L” output voltage on pins DTA_OUT, DTA_RDY IOL = + 1 mA VLH – – 0.1 VDD V “H” input current on pin CLKS IIH IIL IIH IIL IIH IIL – – 50 µA – 200 – – µA – – 200 µA – 50 – – µA – – 50 µA – 200 – – µA Input capacitance Input current Input high voltage Input low voltage Input hysteresis “H” output voltage on pins DTA_OUT, DTA_RDY IOH = – 1 mA “L” input current on pin CLKS “H” input current on pin DTA_IN “L” input current on pin DTA_IN “H” input current on pin CS “L” input current on pin CS Data Book 6 2003-05 KP100 Electrical Characteristics (cont’d) Parameter Symbol Limit Values min. typ. max. Unit Input voltage HIGH level CLKS, CS, DTA_IN VIH 4.0 – – V Input voltage LOW level CLKS, CS, DTA_IN VIL – – 1.0 V Input hysteresis on pins CLKS, CS, DTA_IN VOH – VLH – 0.5 – V SPI Timing Tolerances Parameter CS lead time CS lag time CLKS “H” pulse width CLKS “L” pulse width DTA_IN setup time at pin DTA_IN DTA_IN hold time at pin DTA_IN DTA_OUT output delay time at pin DTA_OUT Clock frequency CLKS Clock cycle time DTA_OUT TRI-STATE® delay time Symbol Limit Values Unit min. typ. max. tlead tlag tWH tWL tSU tH tD 250 – – ns 250 – – ns 880 – – ns 880 – – ns 200 – – ns 200 – – ns – – 200 ns fCLKS tC tZ – – 500 kHz 2 – – µs – – 200 ns – 128 – µs – 16 – µs – – 1 µs – – 1 µs – – 100 ns – – 200 ns DTA-RDY Timing DTA_RDY cycle time DTA_RDY pulse width DTA_OUT status valid setup time DTA_OUT status valid delay time DTA_RDY fall time DTA_RDY rise time Data Book tCDR tWDR tSUDO tDO tFDR tRDR 7 2003-05 KP100 Transfer Function The general relation between output code and pressure is given by the formula p Y(p) = a + b ⋅ ----------kPa c [ digit ] Interface description The KP100 digital interface consists of the pins DTA_IN, CLKS, DTA_OUT, CS and DTA_RDY. The interface is active when CS is low. At the DTA_RDY pin a pulse of approx. 16 µs appears with a frequency of 7.8 kHz. The rising edge of this pulse indicates that the output register has been loaded with a new 16 bit wide data word, where the first bit is a parity bit. The data can then be clocked out by applying a clock signal at CLKS. With every falling edge of CLKS the DTA_OUT is updated, starting with the parity, followed by the LSB. After the 16th falling edge the MSB appears at DTA_OUT and the readout cycle is completed. Simultaneously data can be loaded into the KP100 via DTA_IN. The data is clocked in with every rising edge at CLKS. Only the three last bits of the input data are relevant. They are used to select the diagnosis modes and to switch between 4 and 8 MHz operation. After completing a read-write cycle the three input bits can be activated by applying a positive pulse at CS of at least 50 µs. If for example the diagnosis mode 1 has been choosen the corresponding diagnosis value will appear at DTA_OUT in the next read-write cycle. For the simplest mode of operation the CS and DTA_IN pins are pulled to ground potential. Then only the pins CLKS, DTA_OUT and DTA_RDY are needed to read the pressure data, since the power-on condition of the KP100 is to deliver pressure data in 8 MHz mode. Read Write Cycle A complete read write cycle is shown in the diagram below. DTA_RDY and DTA_OUT are KP100 output signals, CLKS, DTA_IN and CS are KP100 input signals. The first 13 DTA_IN bits are don’t care bits. Data Book 8 2003-05 KP100 Figure 3 Diagnosis Features For transmission reliability the first bit of the data word is a parity bit whereas the next 15 bits are data bits starting with the LSB. Parity is odd in normal mode and even in any diagnosis mode. It is calculated only for the 12 MSBs, the first 3 LSBs are ignored. Besides of the parity bit in the output code there are several additional diagnosis features. In detail these are an automatic fuse-check and three diagnosis modes. Automatic fuse-check: Fuses are used for correcting the transfer function between pressure and output code. An additional parity-fuse guarantees that fuse-data is reliable. If a wrong parity is detected the output code will go to FFFFH, which is defined as an error code. The condition is latched, i.e. the error code will be transmitted until the next power on reset. Diagnosis mode 1: This mode puts the sigma-delta converter into an idle condition where it operates without input signal. This is a good method to check the basic analog performance of the chip. An output code of 8020H (± 3E8H) is expected. Diagnosis mode 2: Data Book 9 2003-05 KP100 The sensor array is subdivided into two independent areas. In diagnosis 2 mode the difference signal of the two areas is measured. A drift of the diagnosis 2 value indicates a mechanical damage of one or more cells. For an efficient use of this mode it is recommended to store the initial diagnosis 2 value on the application board (e.g. in the µC flash) already at the production line. Diagnosis mode 3: This mode applies a general reset to the chip and initiates a special self-test sequence, where the complete digital filter part is checked. After programming the diagnosis 3 mode and activating it by a high-pulse at CS, the following 10 read write cycles must deliver the output values listed below: Number 1 2 3 4 5 6 7 8 9 10 Output value (hex) 0000 0000 0000 0000 0900 25E6 4E8D 741B 9135 A664 Note that between these 10 read-write cycles no further CS pulse must be applyed, in order not to end or to restart the diagnosis 3 mode. Also note that no DTA_RDY must be skipped in this mode, since each value will be overwritten by the subsequent value. Any error in these codes indicates an error in the digital circuitry of the chip. Additionally, this diagnosis mode also resets the fuse-check latch. However, a remaining error conditiotion in the fuses will immediately reestablish this latch, so that the output is set to FFFFH. Data Book 10 2003-05 KP100 Figure 4 Serial Peripheral Interface: Timing Diagram Figure 5 DTA_RDY Timing Diagram Data Book 11 2003-05 KP100 Figure 6 Data Book Transfer Function 12 2003-05 KP100 Package Outlines GMX05998 P-DSOF-8-3 (Plastic Dual Small Outline Flat Package) You can find all of our packages, sorts of packing and others in our Infineon Internet Page “Products”: http://www.infineon.com/products. Data Book 13 Dimensions in mm 2003-05