Motorola APX 6000 Service Manual

Theory of Operation: Controller 3-31
3.2.2.1.3 External Switcher 5
The controller board uses an external TI regulator (TPS62110, U6505) to regulate to 5.4V. The
TPS62110 is a 1.5A capable synchronous step down converter. The output is adjusted using a
voltage divider to the feedback pin. The regulator is powered from SW_B+. Figure 3-18 illustrates the
SW5 circuitry. The SW5 circuit also includes or-gate logic that facilitates implementation of current
saving PFM mode when the radio is in standby mode.
Figure 3-18. 5V Switched Power Supply
APX 5000/APX 6000/APX 6000XE/SRX 2200 has Pulse Switching option.
Mode 1: Pulse Frequency Modulation (PFM). A relatively noisy but highly efficient pulsing mode for
Switched power supplies.
Mode 2: Pulse Width Modulation (PWM). Pulsing mode that is cleaner than PFM, used when risk of
RF interference is present which includes both transmit and receive radio modes.
Table 3-6. Pulse Switching Combination
PA_SHTDN 5V_PWM_EN SYN MODE
000PFM
011PWM
101PWM
111PWM
29
L6504
C6560
C6567
V_SW_5
VIN
U6505
TPS62110
VOUT
EN
SYNC
C6567
SW_B+
BGAP_COMP
PA_SHTDN
5V_PWM_EN
30

Motorola APX 6000 Specifications

General

Frequency Range	700/800 MHz, VHF, UHF Range 1, UHF Range 2
IP Rating	IP67
P25 Phase 1 & 2	Yes
GPS	Yes
Encryption	AES, DES
Power Output	1-3 Watts (700/800 MHz)
Operating Temperature	-30°C to +60°C
Intrinsically Safe	Yes
Bluetooth	Yes (Bluetooth 4.0)