mc33794 Freescale Semiconductor, Inc, mc33794 Datasheet
mc33794
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mc33794 Summary of contents
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... The MC33794 is intended for applications where noncontact sensing of objects is desired. When connected to external electrodes, an electric field is created.,The MC33794 is intended for use in detecting objects in this electric field. The IC generates a low-frequency sine wave. The frequency is adjustable by using an external resistor and is optimized for 120 kHz. The sine wave has very low harmonic content to reduce harmonic interference ...
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... RST WD_IN V PWR AGND GND and HEAT SINK PWR_MON V MON _ DD LAMP_GND LAMP_CTRL ISO_OUT ISO_IN MC33794 2 INTERNAL BLOCK DIAGRAM 4 CONTROL LOGIC Ω (Nominal) Ω MUX OUT Ω MUX IN POR REG V DD ...
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... The current is limited to prevent damage to the IC in the case of a short or surge during lamp turn-on or burn-out. LAMP_CTRL ISO-9414 NC ISO_IN ISO_OUT REF_B REF_A TEST NC NC GND NC SHIELD AGND V CC Definition REG is CC MC33794 3 ...
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... DD This output terminal requires a 47 µF capacitor and internal V a regulated 5.0 V for the MCU and for internal needs of the MC33794. This terminal is connected to the ground return of the analog circuitry. This ground should be kept free of transient electrical noise like that from logic switching ...
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... ISO-9141 bus. This terminal connects to the ISO-9141 bus. It provides the drive and detects signaling on the bus and translates it from the bus level to logic levels for the MCU. This signal is used to control the lamp driver. A high logic level turns on the lamp. MC33794 5 ...
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... Method 1012.1) with the cold plate temperature used for the case temperature. 5. Thermal resistance between the die and the printed circuit board per JEDEC JESD51-8. Board temperature is measured on the top surface of the board near the package. MC33794 6 MAXIMUM RATINGS Symbol ...
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... TIF DLY Min Typ Max 4.75 5.0 5.25 8.075 8.5 8.925 4.0 4.52 4.72 5.26 5.55 5.83 – 0.05 – 0.30 0.33 – – 0.53 0.7 – 0.2 – – – 0.2 0.8 – – 40 – – – 58 – 120 – – 8.0 – – 1.0 100 – – – – 5.4 Unit V/V V/V V/V V/V V/V V Ω mA µs V µA µs MC33794 7 ...
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... LP_CAP to LEVEL Gain LP_CAP to LEVEL Offset Notes 7. Verified by design. Not tested in production. 8. Verified by design and characterization. Not tested in production. 9. Current into grounded terminal under test = 1.0 mA. MC33794 8 , -40°C T 85°C unless otherwise noted. Typical values noted 9.0 V ≤ VPWR ≤ ≤ ≤ 25° ...
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... Voltages are relative A Symbol Min RLD DSON ILD LIM 0.7 VLD ON VLD Z LMP 0.1950 MON PWR 0.2200 MON V 0.45 DD_MON I pwr Typ Max – 1.75 3.5 – 1.7 – – 1.4 40 – – 0.20524 0.2155 0.2444 0.2688 0.5 0.55 _ 7.0 _ Unit Ω V/V V/V V/V mA MC33794 9 ...
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... Source (internal MC33794 10 , -40°C T 85°C unless otherwise noted. Typical values noted 9.0 V ≤ VPWR ≤ ≤ ≤ 25°C under normal conditions unless otherwise noted. Voltages are relative A Symbol f STAB f OSC OSCH ...
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... The MC33794 is made to work with and support a microcontroller. It provides two voltage regulators, a Power- ON-reset/out-of-range voltage detector, watchdog circuit, lamp driver and sense circuit, and a physical layer ISO-9141 communications interface ...
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... This section controls the operation of the LAMP_OUT terminal. When LAMP_CTRL is asserted, LAMP_OUT is pulled to LAMP_GND. If one side of an indicator lamp or LED The MC33794 is intended to be used where an object’s size and proximity are to be determined. This is done by placing electrodes in the area where the object will be. The ...
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... This is typically the method used for touch panel applications. The MC33794 does not contain an ADC intended to be used with an MCU that contains one. Offset and gain have been added to the MC33794 to maximize the sensitivity over the range 100 pF ...
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... F VCC 10 nF Analog_IN ( Optional Analog_IN (Optional) Analog_IN (Optional) Analog_IN MCU ISO_Tx ISO_Rx Watchdog Reset GPx Electrode Select Shield Disable MC33794 14 EXAMPLE APPLICATION DIAGRAM +9 to +18 V Indicator Lamp µ 0.1 F 33794 V PWR LAMP_OUT LP_CAP VCC LEVEL VDD ) VDD MON _ PWR_MON LAMP_MON ...
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... Sensors Freescale Semiconductor PACKAGE DIMENSIONS EK SUFFIX CASE 1390-02 ISSUE C PAGE MC33794 15 ...
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... Sensors Freescale Semiconductor PACKAGE DIMENSIONS PAGE SUFFIX CASE 1390-02 ISSUE C PAGE MC33794 16 ...
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... Sensors Freescale Semiconductor PACKAGE DIMENSIONS PAGE PAGE SUFFIX CASE 1390-02 ISSUE C PAGE MC33794 17 ...
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... RoHS-compliant and/or Pb-free versions of Freescale products have the functionality and electrical characteristics of their non-RoHS-compliant and/or non-Pb-free counterparts. For further information, see http:/www.freescale.com or contact your Freescale sales representative. For information on Freescale’s Environmental Products program http://www.freescale.com/epp. MC33794 Rev 9 11/2006 Information in this document is provided solely to enable system and software implementers to use Freescale Semiconductor products ...