Application Note DK90308 / DK90314 Evaluation Kit Scope The DK90308 and DK90314 provide a communications interface between the device and PC. All necessary components for implementing the three application circuits with the user’s bridge sensor are on board. This document describes the board itself and setup of the common application circuits for the DK90308 and DK90314 Evaluation kit. Related Products and Tools MLX90308 Programmable Sensor Interface MLX90314 Programmable Sensor Interface SW90308 Software for MLX90308CCC and MLX90314AB 90308CCC90314AB UsersManual.pdf WWW.MELEXIS.COM Applications Absolute Voltage Output Mode : The device uses an external FET to regulate the supply voltage. The supply voltage is supplied from J2 thru JP3 to VDD1, then the device regulates +5V on VDD using the onboard FET giving a stable output over varied supply voltage. Ratiometric Voltage Output Mode: In this application the output follows the supply voltage; this is used when the device output is tied to an A/D converter sharing the same supply and ground reference. A 4.5V to 5.2 V supply voltage is supplied thru VDD and VDD1 tied together. JP3 MUST BE OPEN FOR THIS MODE to avoid permanent damage to the ch ip. Current Output Mode: In Current Mode the device supplies a 4 to 20mA current range for use as a 2-wire analog sensor. VDD is regulated by the onboard FET from the supply (7V to 35V) thru VDD1. JP3 must be open to separate the interface circuit supply thru J2 from the device current supply thru VDD1. The device supply ground must be floating with respect to the interface circuit ground. DO NOT CONNECT CMN to GND. The DK90308 and DK90314 can also be used to communicate with the MLX90308 and MLX90314 in custom external circuits. For more information about the MLX90308 and MLX90314 consult the device datasheet. 39011yyyyyzz Rev www Page 1 of 5 Oct-2003 Application Note DK90308 / DK90314 Evaluation Kit Demoboard Layout and Jumper Settings Component side view: SO16 DUT Pin Number Test Point Function IO1 Bidirectional I/O 1 IO2 Bidirectional I/O 2 VDD Regulated Supply Input 9 VBN Negative Bridge Input 6 VBP Positive Bridge Input 7 GND Common Power Ground 15 TMP Temperature Sensor Input 8 VMO Voltage Mode Output 12 JP1 TSTB to GND - Factory Setting Jumper Open CMN Current Mode Negative Return 14 JP2 FLT to 39nF - Factory Setting Jumper Shorted COMS Serial Programming I/O 16 JP4 VMO to 10K - Factory Setting Jumper Shorted VDD1 Unregulated Supply Input 11 JP5 VMO to 10nF - Factory Setting Jumper Shorted VCC Regulated +5V Power Supply from board - OFC Offset Control Output 5 FLT Filter Pin 4 J2: +12V Power Supply +12V Terminal - J2: + Power Supply Ground Terminal - 39011yyyyyzz Rev www Jumper Function +12V Supply to VDD1 - Absolute Voltage Mode - Jumper shorted - Ratiometric Mode – Jumper open JP3 - VDD1 will be shorted to VDD - Current Mode – Jumper Open Cau tion: Device may be permanently damaged if this Jumper is not set correctly. Page 2 of 5 Oct-2003 Application Note DK90308 / DK90314 Evaluation Kit Schematic 39011yyyyyzz Rev www Page 3 of 5 Oct-2003 Application Note DK90308 / DK90314 Evaluation Kit Typical Connection Schemes Absolute Voltage Output Mode: +5V Source TO SERIAL PORT of PC REG Power Supply 7.5V to 20V DUT SO16 Output Voltage Users Bridge Sensor Note: JP3 shorted for Absolute Voltage Mode Temp Resistor (optional) Ratiometric Voltage Output Mode: +5V Source TO SERIAL PORT of PC 4.5V - 5.2V Input Power Supply REG Power Supply 7.5V to 20V DUT SO16 Output Voltage Users Bridge Sensor Note: JP3 Must be open for Ratiometric Voltage Mode Temp Resistor (optional) 39011yyyyyzz Rev www Page 4 of 5 Oct-2003 Application Note DK90308 / DK90314 Evaluation Kit Current Output Mode: +5V Source TO SERIAL PORT of PC REG Power Supply 7.5V to 20V 4 - 20 mA Output Current 7V - 35V Supply DUT SO16 Note: Do not connect CMN to GND Users Bridge Sensor Note: JP3 Must be open for Current Output Mode Temp Resistor (optional) External Circuit Communication: +5V Source TO SERIAL PORT of PC REG Power Supply 7.5V to 20V Connect to Pin16 of Device in external circuit DUT SO16 Note: This is the minimal connections necessary for communication with a device in a circuit external from the application board. The board can only connect to one device at a time therefore the local device socket U4 must be empty when connected to an external circuit. All other connections to the external circuit are subject to which output mode is required and must be determined by the user. 39011yyyyyzz Rev www Power Supply output when JP3 is shorted Page 5 of 5 Connect to GND of external circuit Note: COMS line should be kept as short as possible and free of noise to avoid misprogramming of the Device. Oct-2003