EE 330 Final Design Projects Spring 2015

Transcription

1 EE 330 Final Design Projects Spring 2015 Students may work individually or in groups of 2 on the final design project. Partners need not be in the same laboratory section. Please the name of your group members and rankordered project preferences to: chinwen@iastate.edu Please send only one request per group. In the rank-ordering, please submit your top 3 choices. At most 3 groups will be assigned per project on a first come first serve basis. Selection time will start at 8:00 p.m. on Monday April 6. Any requests with a time-stamp prior to 8:00 will be placed at the bottom of the priority list. We will try to notify you about final project selections by 8:00 a.m. on Tuesday April 7. Please start early on your project, and recognize that some projects may require a bit of research and on-your-own learning. If you get stuck on how to accomplish a task, please consult with either TA or with the course instructor for guidance on how to resolve issues that may arise. READ each project carefully and thoroughly! You cannot switch projects once you have been assigned to the project. Project 1 Digital Alarm Clock with Battery Backup Project 2 Monophonic Keyboard Project 3 Laser Controlled Track Following Car Project 4 LED Display Device Project 5 Voice Controlled Light Controller Project 6 Digital Potentiometer/Amplifier/DAC Project 7 Transceiver Block Project 8 Laser Reaction Game Project 9 Power and Power Factor Meter

2 Project 10 Traffic Volume and Velocity Monitor Project 11 Automatic room light controller with a visitor counter Project 12 Self-Defined Project 1 Digital Alarm Clock with Battery Backup In this project, design an alarm clock integrated circuit in a 0.5u CMOS process which meets the following requirements. The design should be complete through post layout fabrication. 1. The time and the alarm time are programmed by the user. The time is input as typical of most digital alarm clocks with the buttons on the device. This does not need to have provisions for date, time zones or daylight savings time. 2. Assume a power supply comprised of a transformer and a rectifier/ voltage regulator shown below is available. The input to the transformer is that standard 60Hz line voltage. The voltage regulator can provide a constant 5V DC output voltage. The 60Hz line frequency is to be used as the time base in the clock when power is available. 120 VRMS 60Hz 120:5 Rectifier and Regulator 5V DC 3. Assume that when power goes out that there is a 9V battery backup that can be used to keep the clock and alarm functioning. A time-base (sometimes called an oscillator) needs to be built to serve as the clock when the line power is lost. It is not necessary that the time be real precise when the power is off. If the time base varies by +/- 20% when the power is off, that is acceptable for this project. 4. When the time matches the alarm time, an alarm is sounded until being turned OFF or SNOOZE is press ed. SNOOZE delays the alarm for 10 minutes at which time the alarm sounds again. Inputs

3 Alarm Program enable allows alarm to be programmed Time program enable allows time to be programmed OFF- turn off the alarm UP button for adjusting hours/min of time or alarm up one count DOWN button same as above but down SELECT button Accepts value and stores if in program mode. When it in programming mode, hours are selected first, and once SELECT is pressed, the minutes can be altered. A second press of SELECT resumes operation as normal. SNOOZE button- delay the alarm for 10 minutes from it last went off. Outputs LCD display common of digital clocks including hours and minutes. Assume 24 hour military clock. using whatever LCD display you want. Specify the display by commercial part number. A display that has all 6 segments in a single package will require considerably less pins on the IC. Alarm hooked to whatever annoying device will get the person awake. But you must specify exactly what the device is along with a commercial part number and its specifications. Project 2 Monophonic Keyboard This project is to design an integrated circuit in a 0.5um CMOS process that preforms as a monophonic piano ( ideally only one key can be pressed at a time). The design should include layout and post-layout simulation results. The frequency of the output will be based on the frequencies of the keys of a standard 88-key piano. Should the user press more than one key at a time, the piano should be robust in that it will not cause permanent damage. You can specify what the output will be if more than one key is pressed at a time. Your piano should have the ability to play at least 3 octaves of keys (36 consecutive keys). The output should be relative to ground and should be approximately 1V p-p when a key is being played. The output impedance should be less than 10K. You will have one input clock signal available at any frequency you choose. The number of pins on the IC is limited to 24 max. The shape of the output waveform should be something that is reasonably pleasant to listen to but the shape and amplitude should be the same for each note. Unfortunately, square waves are not pleasant

4 to listen to. One way to control the waveshape is to use a DAC to generate a sine wave or a wave similar to that coming from a violin or some other musical instrument. A DAC can be formed from a series of resistors by tapping into different nodes in the series. A DAC with 16 resistors or 32 resistors can be easily built with a serpentine resistor with tap points at the edges of the serpentine.

5 Project 3 Laser controlled track following car Design a laser-controlled tracking controller for a modified RC car. The RC car will be modified by disabling the RC control function and simply using the car for its movement and steering. The car should be designed to follow a specially constructed track. A segment of the track is shown below. The width of the black stripe is 2. The white on the sides of the stripe will be highly reflective. Gradual curves in the track will occur to eventually form a closed loop. Your goal should be to see how fast you can navigate this track. Once a verbal start command is issued, you must be able to start the car from 20 feet away with a laser pointer. Once the car starts moving it will have to navigate a nominally circular track with no directional assistance from you. You should include speed control with a laser pointer as well. Your design should keep the car on the track without any user input. You may not use a microcontroller. Project 4 LED Display Device This project is do design an integrated circuit that can display a short message on a 7-segment display. The message should be up to 25 characters long and the display should cycle through the message with one character being displayed every 1 sec. After the message is complete, there should be a 5 second delay and then the message should be repeated. This should continue indefinitely. There should be a small number of push buttons that serve as control inputs. The modes of operation should be: Program, Set, Scroll. You may have at most 5 control pins. The circuit should be designed to operate with a specified display device. The only components that should be attached to the IC should be the display device, a battery, and up to 5 SPST switches. You may add up to 5 LEDs to facilitate programming.

6 Project 5 Voice control Light Controller This project involved the design of an integrated circuit in a 0.5u CMOS process that can be used to control a Triac for turning on lights in response to a voice command. The controller should handle up to a 500 watt load. Assume you have available a 5V dc power supply. Assume you have a phototransistor that is available as a light sensor. If the light level is above a predetermined level, the lights should be able to be turned on with a SPST switch. Pressing the SPST switch a second time should turn the lights off. If the light level is below a predetermined level, they should be turned on by a voice command. Assume a microphone input is available to your system for the purpose of the voice control. Specify a commercial microphone that you will use in your design. Also specify a commercial Triac that will be used for the control of the light. When activated by voice command, they should turn off automatically after 30 seconds after the last recognized voice command.

7 Project 6 Digital Potentiometer/Amplifier/DAC This project is for the design of a digital potentiometer/amplifier/dac integrated circuit. The design should include layout and post-layout simulation results. Design a multi-purpose digitally controlled analog building block. This structure can serve as a digital potentiometer, an inverting or noninverting amplifier and a DAC depending upon the state control inputs. A method of designing the operational amplifier will be provided to you by your TA. Assume V DD =2.5V and V SS =-2.5V. The state control signals A O and A 1 will identify one of four states of operation of this device. The operation control signals C O, C 1, C 2 and C 3 are used to control the characteristics of the device in each of the four states. When A O and A 1 are high, the circuit is to perform independently as a digital potentiometer and an operational amplifier. The digital potentiometer should have 16 taps, each with a nominal impedance of 5K. When A 0 is high and A 1 is low, the circuit is to perform as a 4- bit DAC where the op amp is connected in a unity gain configuration to a tap on the potentiometer and the DAC output is determined by the control settings on the potentiometer. The DAC input, often termed V REF should be connected to one end of the resistor string and the other end should be grounded. When A 0 is low and A 1 is high, the circuit is to perform as a programmable inverting finite gain amplifier. One end of the resistor string should go to the op amp output, the wiper to the - input and the other end of the resistor string to the input. Finally, when A 0 is low and A 1 is low, the circuit is to perform as a programmable noninverting finite gain amplifier. The digital potentiometer is similar in principle to the Maxim DS 1666 but with a reduced number of taps, with parallel rather than serial control of the tap position, and with a linear taper rather than an audio taper.

8 Project 7 Transceiver Block This project is for the design of a transceiver integrated circuit. The design should include layout and post-layout simulation results. Serial channels are widely used for communicating between computers that may be a few feet apart of on the other side of the world. Invariably the data that is to be transmitted is parallel data so a parallel to serial conversion is needed to get the data ready for transmission and a serial to parallel conversion is needed to convert the data from serial data to parallel data at the receiver. Invariably the data is transmitted from a synchronous system on transitions of a clock and invariably the data at the received is synchronized relative to a clock at the receiver. Unfortunately the two clock frequencies may not be exactly the same and unfortunately it is generally considered impractical to transmit the clock signal to the output so the clock must be recovered from the serial data stream itself. This is often done with a phase-locked loop (PLL) at the receiver which contains an internal voltage controlled oscillator (VCO) that must be locked to the input data sequence. The recovered clock is simply the output of the VCO in the PLL. The PLL must obtain regular measurements of the phase difference between the VCO output and the data input to maintain lock. It is common in many applications to have periods of time where no data is available and during these intervals, long strings long serial strings of 0 s or 1 s must be transmitted. Unfortunately, it is difficult (actually impossible) for the PLL to maintain lock in the absence of transitions on the incoming data stream. To circumvent this problem, the parallel data is often coded prior to serial transmission to guarantee that there will be ample transitions in the transmitted data to recover the clock. Of course, the received data must be decoded at the output to recover the intended data sequence. 8B: 10B and 4B:5B coders are often used for this purpose. In an nb: (n+1)b coder, an n-bit word is converter to an n+1 bit word with a fixed mapping that will guarantee that the maximum number of consecutive 0 s and 1 s in the transmitted data stream is small (like 3 or 4) irrespective of the nature of the input data. In many communication channels, data itself is arranged in packets in which a fixed number of bytes are put together sequentially to form a packet. A header is generally placed at the front of each packet. This header serves two purposes. One is to give information about where the packet is to go or where it comes from. The second is to allow for synchronization of the packet so that the bytes within the packet can be appropriately framed. The design of transceivers which perform these functions is widely undertaken in industry but it is beyond the scope of this course. This project will focus on a part of a transceiver block associated with the encoder and decoder. The PLL that is usually used for clock and data recovery is not a part of this project. Details follow. a) Devise a 4B-5B coding scheme that will guarantee at most 3 consecutive 0 s or 1 s for any input data sequence. b) Design a circuit that will take an 8-bit wide parallel data sequence at 10K bytes/sec and serialize it using the 4B-5B coding scheme you devised in part a). You may assume that a 10KHz clock is present that is synchronous with the input data. c) Design a receiver that will take the serial data string, decode it, and recreate an 8-bit wide data sequence at the output. d) Design a comma detect circuit that will allow for proper framing of the received data. The comma should be a 10-bit code that can not represent any data sequence. The comma

9 would be inserted in place of a byte in the transmitted data stream for synchronization and the receiver should frame the received data relative to the detected comma whenever a comma is detected. After the comma is detected, the received should be in synch with the input data sequence.

10 Project 8 Laser Reaction Game Design a laser, build, and demonstrate a laser beam reaction game to see how fast players can react to a sequence of visual cues. In this project, you will create a rectangular 3 x 3 grid of Lamp:photo detector pairs spaced on a wall at a distance of 24 inches from each other. The middle detector pair will have a second lamp of a different color. The player will stand or sit at a distance of 8 feet or more from the wall. A laser pointer will be used to play the game. Whenever game is complete or whenever it is time to start a new game, the middle lamp that is a different color will be lit. The player will start the game by shining the laser at any of the 9 photo detectors. A random sequence of lamps will then be lit and the reaction time to shoot the light sensor adjacent to the lamp that is lit will be measured. After the target is hit, the lamp will go off. This will be repeated 8 times. After the 8 th lamp goes off, the game is over and the total reaction time is to be displayed on a 7 segment display in seconds. Once the reaction time is displayed, the game should be restarted. The reaction time of the previous player should remain on the display until the following player completes playing the game. If the components you need are not available in the electronics parts shop, you will need to order the early enough to complete the design. Project 9 Power and Power Factor Meter There is often considerable interest in knowing the relationship between real power, reactive power, and power factor. Unfortunately low-cost power factor meters are not readily available. In this project, you are to design a circuit that serves as a power factor meter and that can be used to easily calculate the power. Assume you have an input voltage signal that is either single-phase or three phase that varies between 100VRMS and 450VRMS. You may specify an existing clampon current sensing coil that provides an analog output waveform that is proportional to current. Design a circuit that will provide on the output both the power factor and the RMS voltage. The power factor resolution should be 0.05 for power factors of between -1 and 1. The RMS voltage should have a resolution of 10V over the specified range. The user should select one of 4 modes. Single phase, Single phase complimentary, 3-phase Y, and 3-phase. The output should be displayed on a 4-digit 7-segment display. You must specify the display that you will be driving. The output may alternate between PF and RMS voltage with a push-button selection. Project 10 Traffic Volume and Velocity Monitor Traffic is regularly monitored on roadways to assess the level of usage and the stress placed on the roadway. Three factors are of primary interest, specifically weight, traffic volume, and speed. The pneumatic road tube sensor (PRTS) is often used as a sensor for obtaining traffic volume and speed data. The PRTS is placed across one lane of traffic. Sensing traffic volume with a PRTS is complicated by the observation that some vehicles have two axles (car, motorcycle, and some trucks) whereas other vehicles have 5 or more axels. Also, the wheel base varies from one vehicle to another. Use of the PRTS is complicated a bit more by the observation that occasionally two vehicles have a very small spatial separation. In this project, you are to design a Traffic Volume and Velocity Sensor integrated circuit that serves as a controller for the velocity and volume measurements. Two PRTS sensors should serve as inputs along with a reset button. You may specify the distance between the PTRS sensors. The controller should drive a 4-digit 7-segment display. A mode select input should be provided that will allow assessment of the following:

11 Mode 1 Mode 2 Mode 3 Mode 4 Mode 5 Mode 6 Mode 7 Total number of vehicles since last reset Elapsed time since last reset Average velocity of all vehicles since last reset Maximum velocity of any vehicle since last reset Number of automobiles Number of motorcycles Number of Semi trucks You may specify how the user enters the mode select but some indicator of which mode is being displayed should be provided. You should specify a commercial 7-segment display that will be driven directly by the integrated circuit. You must make a clear statement on assumptions that are made on how to detect different classes of vehicles. Project 11: Automatic room light controller with a visitor counter Description: Wastage of electricity is a serious problem nowadays. In our classes and office, we see that lights and fan are kept on even if there is nobody in the room. This happens due to people forgot to turn their off when leaving the room. There are two major parts for this project. The first part is Visitor Counter. The Visitor Counter is used to measure the number of people in the room. Assume a light curtain is placed across the door at waist height to measure when people enter the room. The output of the light curtain is a Boolean high signal when the light curtain has a blockage and a Boolean low when there is no blockage. This type of sensor works quite well if people agree to walk through the door at a fixed velocity without waving their hands too much and agree to provide a reasonable spacing between two individuals but can give errors when those entering or leaving act somewhat irregularly. You should identify and describe a reasonable criteria for identifying whether a person enters or leaves the room with a goal of determining the correct number of people in the room most of the time. A second input will be from a motion detector. If the motion detector detects no movement in the room for over 3 minutes, it will reset the number of people in the room counter to 0. This will help minimize accumulative errors. The number of people in the room should be displayed on a 4-digit 7-segment display. You should specify which commercial display device that the circuit will drive. The controller should also have a light control. When there are no people in the room, as determined by the motion detector, the light should be off. A delay of 30 seconds should be made from the last detectable motion in the room until the lights turn off. Anyone interrupting the light curtain or any detected motion should always turn the light back on. The output of the light controller should control a triac. Specify the triac that will be used so that the output of your circuit can be directly connected to the gate trigger terminal of the triac. The load driven by the triac must be at least 500W at 120V RMS.

12 Project 12 Self-Defined This project will be personalized to the individual interests of the student. proposals for the self-defined projects should be approved by the course instructor. All