Chapter 2: Functional Description - GE BiliSoft Service Manual

Led phototherapy system

Hide thumbs Also See for BiliSoft:

Operation and maintenance manual (48 pages)

Table Of Contents

Table of Contents

EMI Filter

AC 110 - 240V

2 Fuses

Chassis

Ground

Stand By

Switch

12V Lamp

AC power is fused and filtered by the EMI Filter before it is converted to 12V DC by the Power Supply and

delivered to the Control PCB. The Control PCB consists of three identical buck regulator circuits that are

configured as constant voltage/constant current sources with the ability to adjust the constant current source

output to the LED's. The Control PCB drives three pairs of LED's on the LED PCB and the 12V fan. The LED PCB is

only enabled when power is supplied, the Standby Switch is "On", the Pad Shutter Switch is closed and the

solid-state thermostat on the LED PCB is not tripped. When the solid-state thermostat on the LED PCB is

tripped, the fan still gets 12V to help cool the box. The Control PCB also delivers 12V to the Standby Switch

lamp. When the LED current sensor on the Control PCB detects that at least one pair of LED's is not working

properly, the LED module failure indicator on the Front PCB blinks. When the thermostat on the LED PCB is

tripped, the unit overheated indicator on the Front PCB lights. Whenever power to the LED PCB is "enabled", the

hour meter gets the signal to count hours. See the schematic on the following page for more detail.