1. Team 4 Baby Peas “Pulse Early Alarm Sensor”
Chris Ramirez
Benjamin Goolsby
Xin Tong
Yowwu Lin

2. What is Baby Peas ??? Infants are weak
Traditional monitors do not tell the whole picture
Empirical data is needed
Biomarkers can give peace of mind

3. Motivation Motivation behind Product
SIDS
Infant’s insignificant ability to maintain homeostasis
Unable to express precise problems
Motivation behind education and skill set
RF design
Software design
Medical field

4. Design Approach SAFETY !!!! Human Computer Interface Usability
Functionality
Pulse
Temperature
Oxygen
Position

5. Specifications

6. Design Decisions Low Power Wireless Ease of implementation
Vendor Support
Low Cost

7. Subsystems
Sensors
Comms
Power
Central Processor
Mobile Application

8. Hardware Block Diagram
CC2541 Microcontroller Bluetooth BLE v4.0 RF module circuit
BLE V4.0 compatible display device
Heart Rate / Blood Oxygenation Sensor Circuit
Body Position Sensor Circuit
Skin Temperature Sensor Circuit
Coin Cell Battery
DC-DC regulator circuit

9. Central Processor Low Power Small and Mobile
Interface capability with multiple sensors
Interface capability with wireless devices

10. CC2541 Bluetooth SoC solution
SensorTag and Keyfob development kits valuable for reference design
8051 MCU architecture
Five-Channel Direct Memory Access
I2C, SPI interfaces

11. Peripherals Pulse Oximeter Temperature Sensor
Measures blood oxygen saturation along with heart rate
TI AFE4490
QFN package
3V-3.6V
Temperature Sensor
Measures the temperature on Skin surface
TI TMP006
Wafer Level Chip Scale
2.4V-5.5V

12. Peripheral technical specs
Body Position Sensor
Invensense MPU6000
Gyro + Accelerometer
3 axis for each
Capable of SPI and I2C interface
QFN package

13. Communications

14. Bluetooth Low Energy

15. POWER Texas Instruments TPS62740 step down DC-DC converter
2MHz switching
Selectable output voltage range 1.8v-3.3v
Efficiency of 95%

16. Power Schematics

17. Power solution 2 Linear Tech LTC3534 Buck-Boost DC/DC Converter
2.4v-7v input range w/ 1.8-7v output
Use just 1 CR2032 battery

18. Buck-Boost Schematic

19. CC2541 Schematic

20. Sensor Schematics

21. Printed Circuit Board
Eagle Cadsoft

22. User Interface Design Ease of use
Navigation
Menus
Conducive to the purpose of the device
Responsive

23. Software Flow Charts

24. Software UML Chart

25. Ikea Instruction

26. Concept Design

27. Firmware Block Diagram
Sensors
Start
Sample Data
Setup and Init Registers
Setup and Init SPI/I2C buses
Export to Bluetooth

28. Build
Soldering QFN packages and crystal oscillators w/ hot air pencil under 10x microscope
Solder remaining components with solder iron.

29. Test DC-DC Regulators CC2541 TMP006 MPU-6000 AFE4490
Mobile Application

30. Work Division Goolsby Lin Ramirez Tong Sensors X Bluetooth CPU
Software
Mobile App
Board Design
Power

31. Bill of Materials Item: Price (USD): Microprocessor CC2541 Free Sample
AFE Free Sample
MPU $10.72
TMP Free Sample
TPS Free Sample
PCB x $132
Eagle Hobbyist Version $170
Sensor Tag $25
CC2541 Debugger $99
TI sponsor $-175
Miscellaneous $100
Total so far… $412.72
Expected Total $600.00

32. Project Schedule

33. Project Progress

34. Remaining Problems Everything Board Layout learning curve
RF PCB Layout precision
Understanding Bluetooth Stack protocols
Firmware loading and timings
Mobile application learning curve
AFE4490 analog frontend schematic capture

35. Thanks Dr. Chan Cadsoft Eagle staff Texas Instruments Dr. Richie
Ben’s parents
Chris’ wife
Xin Tong
Yowwu Lin
Christopher Ramirez
Ben Goolsby

36. Any Questions ????