KP110 Absolute Pressure Sensor IC Programmable Temperature Compensation and Calibration On-Chip Signal Conditioning Low Cost Bare Die Version KP110 Data Sheet 357 Features • Ratiometric analog output • Programmable transfer function performed by customer • High accuracy over a large temperature range up to ± 1.2 kPa (10 ... 85 °C) • CMOS compatible surface micromachining • Bare die • Specific transfer functions programmable • Broken wire detection Type Ordering Code Minimum Order Quantity KP110 Q62705-K432 1 Wafer Product Description The KP110 is a miniaturized absolute pressure sensor IC based on the capacitive principle. It is surface micromachined with a monolithic integrated signal conditioning circuit realized in the state-of-the-art 0.8 µm BiCMOS technology. As the KP110 is a high precision IC for cost critical solutions. High accuracy and high sensitivity enable the dedication in automotive applications as well as consumer products. In the automotive field the manifold air pressure (MAP) and barometric air pressure (BAP) are important parameters to compute the air-fuel ratio provided to the engine and for controlling spark advance to optimize engine efficiency. Data Book 1 2003-05 KP110 Pad Configuration (top view of die) Figure 1 Pad Definitions and Functions Pad No. Symbol Function 1 SERIAL_CLK/ PROG_VOLT External clock for communication/ Programming voltage 2 DTA_IN Serial in 3 DTA_OUT Serial out 4 VCC Supply voltage 5 (GND) Alternative ground pad 6 VOUT Analog pressure signal output 7 GND 0 V circuit ground potential The pads described in the shaded rows of the table above are used during calibration only. Data Book 2 2003-05 KP110 Die Data • • • • • • • • Semiconductor material: Silicon Surface passivation: Silicon-Nitride Die thickness: 675 µm Die dimension: 4.30 mm x 3.34 mm Pad metallisation: AlSiCu Size of the bondpads (area free of passivation): 200 x 200 µm Rear side metallisation of the chips: no used The rear side of the chip is electrical connected with GND-Pad Figure 2 Data Book Functional Block Diagram 3 2003-05 KP110 Functional Description Digital Programming Interface The KP110 digital interface is a 3 wire interface consisting of Data_In, Data_Out and Clock. A write cycle needs 13 Clock cycles. With the first 12 rising edges of the Clock the signal on Data_In is clocked into a shift register. The first 3 bits are interpreted as a register address, the last 9 as data bits. The address and the data word are starting with the LSB, respectively. During the falling edges of the first 11 Clock cycles the Data_In must be low. The falling edge of the 12th Clock cycle enables the write frame, at this time Data_In must be high. A 13th Clock cycle is needed for internal purposes, the signal at Data_In is ignored. Simultaneously to the write cycle, a read cycle at Data_Out is performed. The signal at Data_Out is structured the same way as at Data_In, i.e. 3 address bits and 9 data bits. The selected register for reading depends on the content of the TESTREG register. The first valid bit at Data_Out appears with the 13th rising edge of the Clock of the previous write frame. The following figure shows the timing diagram: Figure 3 Data Book Timing Diagram 4 2003-05 KP110 The table below shows the internal registers of the KP110. For the shaded registers PROM cells exist. The PROM cells are used for permanent programming of the calibration data. In addition to the registers in the table below a 12 x 9 bit RAM table exists for the linearization and definition of the analog pressure signal. This RAM table is also overlayed by PROM cells. To write a 9 bit word to the RAM table at first the data content must be written into the MEMDAT register. In a further write cycle the desired word is addressed by the 4 LSBs of the MEMCTL register. Register Function MEMDAT Data bit 0 to 9 MEMCTL Selection of register of linearization table GLOBOFF Global offset compensation FUSE_NR Fuse number TESTREG Selection of register for read cycle TGAIN Temperature gain compensation (linear and square) TOFFL Linear temperature offset compensation TOFFQ Square temperature offset compensation MODEREG Selection of registers for programming of PROM The shaded registers in the table are overlayed with PROM Nonvolatile Memory Each PROM cell consists of a thin polysilicon wire located in a small evacuated cavity. The cells are called HR-fuses. In order to write a logic "1" to a HR-cell the wire has to be cut with a current pulse. Since the current can reach up to 100 mA only a single HR-fuse can be programmed at a time. The desired bit within a HR-fuse register is addressed by a register called FUSE_NR. In case of the linearization table the desired PROM register itself is addressed by the MEMCTL-register. In order to program the GLOBOFF, TGAIN, TOFFL and TOFFQ register the MODREG-register is used for addressing. After the correct addressing of PROM register and bit a fuse pulse has to be applied to pad 1. The requirements for the pulse voltage, length and slew rate are given in the electrical characteristics. The exact sequences for RAM/PROM reading/writing are available on request. Data Book 5 2003-05 KP110 Calibration The GLOBOFF register is needed to adjust the sensor cell to the internal A/D converter range. The TGAIN, TOFFL and TOFFQ registers are used for the temperature compensation. These registers together with the linearization table have to be programmed to achieve the full sensor performance. For a proper calibration of the compensation registers and the linearization table it is proposed to measure the sensor at a minimum of two different temperatures (e.g. 25 °C, 100 °C) and 3 pressures, depending on the desired pressure range. To set up an appropriate calibration sequence support of the IFX sensor application group is available. Maximum Ratings Parameter Supply voltage Supply voltage1) Supply current Ambient temperature Storage temperature Burst pressure Voltage at pad DTA_IN Voltage at pad SERIAL_CLK/ PROG_VOLT during clock mode Voltage at pad SERIAL_CLK/ PROG_VOLT during fuse mode Symbol Limit Values Unit min. max. VCC VCC ICC TMAX TS pBURST VDTA_IN VSERIAL_CLK – 0.3 6.5 V – 6.52) 16.5 V 10 mA – 40 140 °C – 60 150 °C VPROG 400 – 0.2 3.2 V – 0.2 3.2 V – 0.2 12 V 2 mA "H" output peak current at pad DTA_OUT IOHP "L" output peak current at pad DTA_OUT IOLP kPa –2 mA 1) 1h@70 °C 2) Reverse polarity; ICC < 300 mA Note: Stresse above those listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Data Book 6 2003-05 KP110 ESD Protection Human Body Model (HBM) tests according to: Standard EIA/JESD22-A114-B HBM (covers MIL STD 883D) Parameter Symbol ESD-Protection VESD Pins VCC, GND, VOUT Calibration Pins Limit Values min. max. – – ±2 ±1 Unit Notes kV R = 1.5 kΩ, C = 100 pF Operating Range VCC = 5.0 V, GND = 0 V, TA = -40 °C to +140 °C, unless otherwise specified Parameter Supply voltage Symbol 1) Output current (pad 6) 2) Sink Source2) Operating temperature Minimum rated pressure Maximum rated pressure Pressure span Lifetime Limit Values Unit min. max. VCC IOUT 4.5 5.5 TA pN, MIN pN, MAX PSPAN tLT – 40 140 °C 10 50 kPa 102 120 kPa 70 105 kPa V 0.25 0.25 mA mA 15 year 1) The output of the sensor is ratiometric to the supply voltage VCC within its specified range of 4.50 to 5.50 V. 2) Sink: Current into device. Source: Current driven by device Electrical Characteristics VCC = 5.0 V, GND = 0 V, TA = -40 °C to +140 °C, unless otherwise specified Parameter Symbol Limit Values min. Output voltage at min. rated pressure1) typ. Unit max. 0.25 0.5 V 4.50 4.85 V Overall accuracy VOUT, MIN VOUT, MAX ACC Ratiometricity2) Rat -25 Response time3) tR Output voltage at max. rated pressure1) Data Book 7 see below kPa 25 mV 5 ms 2003-05 KP110 Electrical Characteristics (cont’d) VCC = 5.0 V, GND = 0 V, TA = -40 °C to +140 °C, unless otherwise specified Parameter Symbol Limit Values min. Output ripple @ f > 1 kHz @ f < 1 kHz Stabilization time4) typ. max. 10 5 15 7.5 mVpp mVpp 20 ms 5 ms tS tUP Power up time Unit 1) The output of the sensor is ratiometric to the supply voltage VCC within its specified range of 4.50 to 5.50 V. 2) Definition: V CC Rat = V OUT ( @ V CC ) – V OUT ( @5 V ) ---------5V for VOUT in the range of 0.1 × VDD to 0.9 × VCC and VCC in the range of 4.50 V to 5.50 V Ratiometric signal error is not included in the overall accuracy! 3) Response time is defined as the time for the incremental change in the output to go from 10% to 90% of its final value when subjected to a specified step change in pressure. 4) Stabilization time is defined as the time required for the product to meet the specified output voltage after the pressure has been stabilized. Input Pad SERIAL_CLK / PROG_VOLT Input voltage (fuse mode) Input capacitance Input current (clock mode) Input current (fuse mode) for 10 ms "H" Input voltage (clock mode) "L" Input voltage (clock mode) Input hysteresis VPROGIN CSERIAL_CLK ICKLIN IVPROG VHSERIAL_CLK VLSERIAL_CLK VCINHYST – 9 – V – – 160 pF –5 – 360 µA 10 – 100 mA 2.2 – – V – – 0.5 V – 480 – mV CDTA_IN IDTA_IN VHDTA_IN VLDTA_IN VSINHYST – 2.5 – pF – – 360 µA 2.2 – 3.2 V – – 0.5 V – 480 – mV Input Pad DTA_IN Input capacitance Input current "H" Input voltage "L" Input voltage Input hysteresis Data Book 8 2003-05 KP110 Electrical Characteristics (cont’d) VCC = 5.0 V, GND = 0 V, TA = -40 °C to +140 °C, unless otherwise specified Parameter Symbol Limit Values Unit min. typ. max. VOH VOL 2.4 – – V – – 0.3 V fCLK tWH tWL tISU tICH tOD 1 – 250 kHz 2 – – µs 2 – – µs 500 – – ns 500 – – ns 0 – 200 ns tENS tENH tVPD 500 – – ns 500 – – ns 1 – – µs PROG_VOLT hold time (At Pad SERIAL_CLK) tVPH 10 – – ms PROG_VOLT slew rate SR 100 – – V/µs Output Pad DTA_OUT "H" output voltage (IOH = 1 mA) "L" output voltage (IOL = -1 mA) Timing and Tolerances Clock frequency SERIAL_CLK CLKS "H" pulse width CLKS "L" pulse width DTA_IN setup time (At Pad DTA_IN) DTA_IN hold time (At Pad DTA_IN) DTA_OUT output delay time (At Pad DTA_OUT) ENABLE setup time (At Pad DTA_IN) ENABLE hold time (At Pad DTA_IN) PROG_VOLT setup time (At Pad SERIAL_CLK) Data Book 9 2003-05 KP110 Transfer Function The sensor can be calibrated with a linear transfer characteristic between the applied pressure and the output signal: VOUT = VCC × (a × p + b) The output is ratiometric. The gain a and the offset b can be calibrated. A feasible transfer function for the KP110 is for example: VOUT = 5.000 V × (0.0106 × p – 0.32666) With the parameters a and b the following calibration is adjusted: pN, MIN = 40 kPa → VOUT = 0.5 V and pN, MAX = 115 kPa → VOUT = 4.5 V (@VCC = 5 V) Figure 4 Possible Transfer Function of the KP110 The output circuit has a low pass filter (min. 1st .Order) with a cut off frequency greater than 500 Hz. The output circuit is protected against short circuit to VDD and GND. Data Book 10 2003-05 KP110 Accuracy Accuracy is the deviation in actual output from nominal output over the entire pressure and temperature range according to figure below due to all sources of error including the following: • Pressure: Output deviation from target transfer function over the specified pressure range. • Temperature: Output deviation over the temperature range. • Aging during operating time The error band is determined by a continuous line through four relevant break points: Break Point (°C) Typical Accuracy (kPa) – 40 ± 2.4 10 ± 1.2 85 ± 1.2 140 ± 2.4 Note: The gained output signal accuracy depends largely on the quality of the mounting and calibration process accomplished by the customer! Figure 5 Data Book Overall Accuracy over Temperature 11 2003-05 KP110 Application Circuit It is recommended, that the circuit of the pressure sensor IC is protected against overload voltage and electro magnetic influences (like shown in Figure 6). The output circuitry acts as a low pass decoupling filter between the output of the sensor IC and the A/D input of the µC. Note: Circuitries of customer specific applications may deviate from this circuitry. Figure 6 Typical Application Circuit of the KP110 Component Range Typ. value R1 R2 C1 C2 20 kΩ < R1 < 100 kΩ 59 kΩ 3.9 kΩ < R1 < 100 kΩ 47 kΩ 0 < C1 < 100 nF 0 nF 33 nF < C2 < 100 nF 100 nF Data Book 12 2003-05