MAXDATA Belinea 101555, Руководство по обслуживанию

Страница: 15 / 52

MAXDATA Belinea 101555
_____________________________________________________________________________________________________________________
4.1.3 Power reference TL431 (TD1)
The TL431 is a 2.5V voltage provider. It could support maximum 100mA current capability. The 2.5V reference was for scaler
MRT MVZ reference. The voltage was very important for this all the function that MVZ have.
4.2 Inverter/Power/Audio Board
This is a specific inverter/Power/Audio module for L5TL monitor with backlight/EE parts/audio function.
4.2.1 Inverter function
The inverter converters 12 Vdc to drive two cold cathode fluorescence tubes. Electrical specification described as below.
INPUT
7.5 mA Rate Output Current per tube
50~60KHz Rated Output Frequency
675 Vrms at 7.5 mA Rated Output Voltage
1100 Vrms Rated Output Strike-on Voltage OUTPUT
20~98 % duty cycle On / Off Voltage
< 0.1 W Off state Input Power
<1. 2A Input Current
11.4~12.6 Vdc Maximum Input Voltage
12Vdc (L5EP) Rated Input Voltage
4.2.2 Adapter
This is a general purpose AC / DC adapter which converter 90~240 Vac to a stabilized DC voltage 12 V
with rated
output current of 3A . Electrical specification described as below
INPUT
< 1 Second Turn-on Delay
< 250mA and 2.0A Rate Output Current
< 120 and 100 mVp-p Output Ripple and Noise
+ 5 / -5 % and Output Voltage Regulation
12 Vdc and 3.3Vdc Rated Output Voltage OUTPUT
< 1.0 W (3.3V 30mA) Standby Input Power
< 50A @ all input range Inrush Current (Cold Start)
< 1.0A Input Current
90~264 Vac, 47~63 Hz Operation Input Voltage
100~240 Vac , 50/60 Hz Rated Input Voltage
4.2.3 Audio amplifier TDA7496
The AN7522 on the power board is a 2 channel audio power amplifier capable of delivering 1W of continuous average power
to an 8 ohms with less than 10% (THD) from a 12 V power supply.
TDA7496 can directly drive 8 ohms speaker, does not require output coupling capacitor, bootstrap capacitor,
or snubber network. Audio line-in are feed into pin 4,8 of the AN7522. The output power is controlled by
the DC voltage of pin 39 from MTV312 I / O port.
_____________________________________________________________________________________________________________________________
111503
Page 15
Confidential -