Motorola APX 6000 - Figure 3-54. Current Distribution Tree for Bluetooth Circuitry

3-70 Theory of Operation: Bluetooth
The host processor operates from a 3.3V LDO regulator (U2402). The 1.85V regulator enables the
3.3V LDO regulator output. The LF receiver IC is powered from a 3.3V LDO regulator (U2402).
Figure 3-54 is a partial current tree showing the flow of current from the battery to the Bluetooth-
related major components sourced by the 3.6V switching regulator on the VOCON.
Figure 3-54. Current Distribution Tree for Bluetooth Circuitry
3.5.2 Bluetooth Clocks
The Bluetooth IC requires a 26 MHz TCXO (Y2204, TCXO_CLK) for the core and a 32.768 kHz
(U6101 pin E2 on vocon, RTC_CLK) slow clock for the USART. This is the same clock used for the
GPS portion of the BT/GPS combination IC.
The host processor IC requires a 12 MHz crystal oscillator (Y2475) clock. The LF receiver IC
requires a 32.768 kHz (U6101 pin E2 on vocon, RTC_CLK) clock.
7.5V Batt
3.6V Switcher
800mA TPS 62050
2.23V LDO
TPS 73601
1.85V LDO
LP38693SD
J4001 pin41
J1001 pin 37
VCP_IN
Vocon
Expansion
P2001 pin 41
TI NL5500
BT/GPS
3.3V LDO
500mA LP2989
J2001 pin 11
JTAG
AS3930A
Low Freq.
ST LIS3331DL
Accelerometer
Logic & Level
8 x Level Shifters
1 x Inverter
Logic & Level
1 x NOR
12 MHz OSC
AT32UC3A
AVR32
16MB SDRAM
SW_B+
V_SW_3.60
VSW_3.6
GPS_BT_3.3V