GE Medical Systems Dash 3000, Service Manual, Page: 206 / 232

ASSEMBLY DRAWINGS: Theory Of Operation
9-18 Dash 3000/4000 Patient Monitor Revision B
2000966-105
Main DC-DC Converter
Section The main DC-DC converter consists of two independent synchronous
rectifier buck regulators with one common controller.
The monitor uses a “point of use” power conversion architecture with +9-
18 V being the main power distribution bus.
Four voltage outputs are developed on the processor/power management
PCB:
• +3.3 V,
• +5 V,
• +12 V, and
• –12 V.
Each one of the four outputs are individually current limit protected
against overload and short circuit.
Battery Subsystem Battery charging and control is accomplished on the Processor/Power
Management PCB.
The battery is a smart battery and features an on-pack fuel gauge.
Optional Thermal
Printer The monitor uses the same 50-mm thermal printer module that is used
in the PRN 50 stand-alone printer. It prints up to four waveforms at
chart speeds ranging from 0.1 to 50 mm/s. The printer software is loaded
independently from the monitor’s software.
In the monitor, the printer module limits its current consumption to stay
within its allocated system power budget.
Speaker
The speaker is used for audible notification of alarms.
Handle Subassembly The handle serves multiple purposes in the monitor. The modular design
enables the user to add adapters for specialized applications.
The Dash 3000 handle houses the optional alarm light. This light is
visible for 360° surrounding the monitor. The light is intended for
applications when the audible notification is not useful or effective, such
as noisy environments (e.g., emergency vehicles) or quiet environments
(e.g., neonatal care areas). The alarm light indicates two levels of visual
alarms:
• Crisis alarms (red LED) and
• Warning alarms (amber LED).
The Dash 3000/4000 handle also houses the two RF LAN antennas
required for the optional RF LAN subsystem.