B+ And +5V Routing For Vocon - Motorola XTS 2500 Service Manual

VHF Radio Power: B+ and +5V Routing for VOCON

3.1.5 B+ and +5V Routing for VOCON

Refer to Figure 3.1-2
Battery
7.5 Volts
(Nominal)
Analog Circuits
Figure 3.1-2. XTS 2500/XTS 2500
Power for the radio is derived from a 7.5 volt battery (UNSW_B+), which is applied to the power
mosfet (Q703 and Q700) in the RF and VOCON sections respectively.
Q700 is a power mosfet switch that provides SW_B+ to the MAKO IC to U500 (the 5V regulator) in
the RF section.
The digital circuits in the VOCON section are powered from regulators located in the MAKO IC. The
MAKO IC provides five software-programmable supplies (VSW1, V1.55, V1.875, V2.9 and VCC5).
VSW1 provides voltage to the 3V regulators (U501 and U502) in the RF section. The initial and
programmed output of VSW2 (C715) is 2.3V. The VSW2 is used internal to the MAKO IC to supply
the 1.875V (V1.875) and 1.55V (V1.55) linear voltage regulators.
6816985H01-F
and the appropriate schematic diagrams in the back of this manual.
RF Section
UNSW_B+
Fuse
RFSW_B+
U500
5 Volts
U501 U502
3 Volts 3 Volts
Digital Circuits
I
/XTS 2000/ATS 3000 DC Distribution (for all other kits)
VOCON Section
UNSW_B+
Q703 Q700
3.6 V (VSW1)
1.875 Volts 1.55 Volts
5 Volts
(V1.875) (V1.55)
(VCC5)
3.1-3
SW_B+
U701
2.9 Volts
(V2.9)
February 14, 2012