User's Manual

MCPS2135 System MonitoringPlanning and PreparationIntroduction

24 MCPS2135 Operations Manual

1.45.4 MCPS2135 Alarm Limits and Protection Circuits

The MCPS2135 series of multicarrier power amplifiers has a wide range of alarm

configurations available. These may be specified to meet the demands of specific

applications. In addition, the MCPA modules have built-in protection circuits to

prevent damage from unintentional misuse. Module alarms may be summarized

and reported to a BTS using a customized interface. This hierarchical system

insures that Spectrian’s MCPS2135 series amplifier systems remain robust with a

minimum of false alarms, but promptly report any real issues to the base station

controller.

The default alarm limit settings and analog protection circuit operation for the

MCPS2135 family of MCPA amplifier systems are summarized below. The

information contained herein is provided for reference only. Guaranteed

specification limits must be negotiated between prospective customers and

Spectrian. There are three levels of the alarm/protection hierarchy:

• Analog Protection Circuits – Configured in hardware design to protect the

MCPA.

• MCPA Module Alarms – Most are software configurable for specific

applications.

• Amplifier System Alarms – Summarizes MCPA and Alarm Management

Module status.

In general, analog protection circuit limits are set by design, and may not be

changed. MCPA alarm limits are software configurable, and may be tailored to

meet customer alarm specifications. Individual MCPA alarms are not displayed

on the module front panel, but they are accessible through Spectrian’s Graphical

User Interface (GUI) software. System level alarms are summaries of the module

alarm status (minor/major/critical), as well as the Amplifier Management Module

(AMM) and the communication link between the modules and the AMM. The

summary set-up is configurable using the amplifier GUI software.

1.1.15.4.1 MCPA Module Analog Protection Circuits

The MCPS2135 MCPA module design incorporates circuits to prevent MCPA

module damage by common misuse conditions. The circuits react automatically to

the conditions shown in Table 3 with the limits set as noted. These limits are not

adjustable by software configuration.

Control Condition Speed Latch

Input Overdrive > 10 dBm @ Input (configured for 57 dB module gain) 2 msec No

Main Amp Overdrive > 4 dBm @ Vectormod Input

35 µsec

Error Amp Overdrive > -7 dBm @ Vectormod Input

35 µsec

Overvoltage Clamp Internal DC line is limited to 28V by linear regulation

up to 30V input

10 msec No

Circuit Breaker > 75 A current draw 25 msec Yes

Table 3: Analog Protection Circuit