Figure 3-50. Current Distribution Tree For Bluetooth Circuitry - Motorola APX 1000 Detailed Service Manual

3-62
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 3-50 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 Main Board.
2.23V LDO
TPS 73601
AS3930A
Low Freq.
1.85V LDO
LP38693SD
TI NL5500
BT/GPS
ST LIS3331DL
Accelerometer
Logic & Level
8 x Level Shifters
1 x Inverter
Logic & Level
1 x NOR

Figure 3-50. Current Distribution Tree for Bluetooth Circuitry

7.5V Batt
SW_B+
3.6V Switcher
800mA TPS 62050
V_SW_3.60
J2301 pin23
J1001 pin 37
P2001 pin 23
VSW_3.6
3.3V LDO
500mA LP2989
GPS_BT_3.3V
16MB SDRAM
Theory of Operation
VCP_IN
Main Board
Keypad Board
12 MHz OSC
AT32UC3A
AVR32
: Bluetooth