Fukuda Denshi DSL-8001, Service Manual

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Main Board and Display Panel Board Description
z Main CPU
Main CPU processes digital filter and analyzes the pulse wave with cuff pressure signal obtained
from actuator control such as pressure pump or constant and exhaust valves or pressure sensor,
and then measures BP. Also, the cuff pressure is constantly monitored. If an error occurs, open
the valve and exhaust the air from the cuff.
DSL-8001 communicates with NIBP module in serial communication via SCIF on main CPU.
Main CPU also controls 7segLED and receives switch input on the display panel board. Main
CPU has a built-in flash ROM and the programs of the main CPU are stored here.
z Sub CPU
Although the main CPU monitors anomalous pressure, the safety may not be guaranteed if the
program of main CPU abnormally functions.Therefore, double safety measures are taken with
the sub CPU monitoring anomalous pressure independently of the standard control. In the same
manner as main CPU, sub CPU has a built-in flash ROM and the program of the sub CPU is
stored here.
z EEPROM
Adjusted data of the pressure sensor is stored in the EEPROM.
z Pressure Sensor
Pressure sensor 1 output is used as a signal to analyze the pulse wave in main CPU. Pressure
sensor 1 output signal is converted into A/D by 24bit
⊿Σ
A/D converter and transmitted to the
main CPU.
Pressure sensor 2 output is used as a signal to monitor anomalous pressure, converted into A/D
by built-in A/D converter in the sub CPU, and its signal process is performed.
z Pressure Pump Drive Circuit
Using PWM the signal of the main CPU, the circuit controls the pump rotation speed and
pressurization rate.
z Constant Exhaust Valve Drive Circuit
The circuit controls the depressurization rate of constant exhaust valve using PWM control signal
of the main CPU.PWM signal converts to DC voltage in smoothing circuit, inputs in constant
current circuit, and performs current control on the constant exhaust valve.
z Rapid Exhaust Valve Drive Circuit
The circuit performs ON/OF control using the main CPU.
z DC/DC Converter
Sup12V power from the DSL-8001 monitor, DC/DC converter independently supplies
main/sub CPU and pressure sensor with power.
z Display Panel Board
Display panel board has an operating switch to actuate NIBP module alone. The 7seg LED on
the board displays BP measurement result and measured pressure value for measurement
detection mode. This function is used only for factory adjustment.
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