NuPower
TM
ULS-25-C01-S01 User Manual
Rev 1.0
9
4.2
DC POWER
The nominal supply voltage for the NuPower ULS-25-C01-S01 is +28 VDC; however, the amplifier module
is able to support operation over a supply voltage range of +11 to +32 VDC.
4.3
GROUND
The signal and power grounds are tied together in the PA module.
4.4
RF ENABLE
This signal is the logic control input that designates whether the unit is in transmit or standby mode. The
RF Enable line is pulled high internally placing the PA module in
standby
mode. If the pin is left floating
(i.e. not connected), the unit will default to
standby
mode.
Grounding the pin (i.e. a voltage below +0.2 VDC) places the unit in
transmit
mode. The user can either
connect the RF Enable line to pins 1 & 2 on the CTRL/PWR interface connector, or an open drain logic line
capable of sinking 500
µ
A to place the unit in
transmit
mode.
4.5
TEMP FLAG
This signal is a logic level output to indicate an over-temperature condition in the NuPower ULS-25-C01-
S01. A logic high (+5 VDC) indicates normal operation, while a logic low (0 VDC) indicates an over-
temperature condition. The NuPower ULS-25-C01-S01 incorporates internal logic circuitry that turns off
the DC bias to the RF transistors.
Caution: The amplifier should be shut down and allowed to cool off when the over-
temperature flag is set high to avoid damage to the module.
