Power consumption report ST72F324 MCU board

1
Bluetooth keyboard Introduction
Feb 2004
MCU / Shanghai
2
Bluetooth keyboard IntroductionAgenda

• Introduction
• block diagram
• Introduction and features
• Reference design using ST72324
• Implementation
• Migrate to the user application
• Plan and schedule in the near future

3
All-in-1 Bluetooth Keyboard block diagram
Bluetooth Module
UART(data)
ST72(F) 324LJ2
STLC 2410
STLC 2150
Antenna
BB_Ready
Key_Press
M28R400CT
Vbatt 3.0V 2.0V
Key_Press, BB_Ready Hand-shake signal
/BT_SHDN
1.8V
3.3V
L6920D
3.6V
2.7V
XC6401FF42
XC6219B332
4
Introduction to Bluetooth (1)

• Bluetooth technology works globally
• works in the globally available spectrum in the
  ISM band (2.4 GHz)
• frequency hop scheme to avoid electromagnetic
  interference
• The gross data rate is 1Mb/s
• Bluetooth Special Interest Group (SIG) is an
  industry group

5
Introduction to Bluetooth (2)

• Bluetooth technology new version
• Version 1.2 released in November 2003
• Adaptive Frequency Hopping (AFH) added reduce
  interference between wireless technologies, like
  cordless telephones, microwave ovens, and
  802.11b/g
• Faster Connections Better user experience
• Backward Compatible backward compatible with
  V1.1

6
Introduction to Bluetooth (3)

• Bluetooth chipset by ST
• 3-chip solution baseband, radio, flash
• 2-chip solution basebandflash, radio
• Bluetooth chipset price
• 4.75/chipset in 2003 down to 3.45/chipset in
  2004, and 2.30/chipset in 2007

7
Bluetooth keyboard features(1)

• Wireless
• Ease of use
• 10 meters range
• 2 batteries powered
• More than 3 months life
• Support both alkaline NiCd NiMH batteries
• HID Bluetooth dongle(transceiver)
• No need to install special software(98,2000,xp)

8
Bluetooth keyboard features(2)

• ST72324L used
• 3.3V operation voltage, low power consumption to
  interface to Bluetooth chips directly
• 188 key-matrix supported, capability to support
  multimedia keys

9
Bluetooth keyboard features(3)

• Advantage disadvantage of Bluetooth
• Advantage good security(compare to 802.11), good
  compatibility-not only for PC,also can be used in
  PDACell phone sectors(compare to wireless
  keyboard using specific protocol, 27M Hz Radio)
• Disadvantage a bit higher price(compare to 27M
  Hz wireless keyboard)

10
Bluetooth keyboard IntroductionAgenda

• Introduction
• block diagram
• Introduction and features
• Reference design using ST72324
• Implementation
• Migrate to the user application
• Plan and schedule in the near future

11
Bluetooth Keyboard block diagram(MCU oriented)
Row input
MCU ST72(F) 324LJ2
Bluetooth Module
UART(data)
Antenna
BB_Ready
Key_Press
Column output
Turn on
Turn off
Key_Press, BB_Ready Hand-shake signal
DC-DC L6920D
Power management XC6219B332
3.6V
2 batteries
12
ST72324(B)L Summary

• 8 to 32K Flash/ROM
• Up to 32 multifunctional bidirectional I/O lines
• Voltage Range 3.0 to 3.6V (Flash), 2.7 to 3.6V
  (ROM)
• Four Power Saving Modes Halt, Active-Halt, Wait
  and Slow
• lt10uA max current_at_ halt mode (lt1uA typical
  current)
• 350/45uA(Flash/ROM) typical current_at_ACTIVE-HALT
  mode

13
Software architecture
Power on
Scan key Output to column Input from row
key pressed
Setup I/O halt
Debounce key
No key pressed
Key pressed
Power on Bluetooth
Send scan-code
Wait for BlueT ready
14
MCU state machine
Short-timeout Active-halt
Make-code sent
Long-timeout Active-halt
Key release
Break-code sent
Key hold
Key press
Halt
Power-on
15
Main components
16
Migrate to the user application

• Key-matrix
• Standard multimedia keys defined, supported
• Capability to define support user-specific keys
• Key-scan library
• Verified, ease users work and time
• Support 188 key-matrix, easy to port to other
  matrix (only several minutes time needed)
• Embedded key-scan function, debounce function

17
Bluetooth keyboard IntroductionAgenda

• Introduction
• block diagram
• Introduction and features
• Reference design using ST72324
• Implementation
• Migrate to the user application
• Plan and schedule in the near future

18
Plan and schedule

• 2004 Feb early March resolve existing problems
• 2004 late March April customer promotion
• 2004 May small amount production