Acer Aspire 1800, Service Manual

Page: 36 / 97

28 Chapter 1
Electrical Characteristics
No
.
Item Symbol Min. Typ. Max. Unit Comment
1
Input voltage INV_PWR 10 16 20 V Note 1
2
Input current Iin -- 0.33 -- A
3 Lamp current IL 3.3 -- 6.8 mA DAC=0V
*Note 2
4 Lamp current IL 2.7 -- 6.3 mA DAC= 0.5V
4 Frequency F 50 60 70 KHz * Note 3
5 Output power Pout -- -- 4.8 W When two lamps total
9.6W
6 Efficiency
η
76% -- -- --
7 Starting
voltage Vs 1600 -- --- V
At 0 ’C
8 Starting time Tvs 1 -- 1.5 Sec
9 Dispoff# 2.8 3.3 3.6 V Backlight on/off signal
0 0.5 0.8 V Low level
10 Limited lamp
maximum
current DAC-
BRIG 0 3.3 V *Note 2
11 PWM signal
*Note 4 INV_PWM 142 150 158 Hz PWM signal frequency
3.0 3.3 3.6 V PWM signal amplitude
30 -- 100 %
12 Lamp current
over-shoot I zero-PK -- -- 20 % Line transient (10.8V to
21V/100us) and turn
on transient
13 Current
Waveform
factor 1.27 1.56 Multipl
e
or *10
14 Unbalance
Rate -15% 0 +15% Mulitpl
e
15 Turn off
current (Hight
side) IHL -- -- 0 A PWM=40%
16 Turn off
voltage Voff -- -- 150Vp
-p V PWM=40%
17 Voltage Rise
time Trise -- -- 300us us PWM=40%
18 Voltage fall
time Tfall -- -- 300us us PWM=40%
19 Lamp current
balance L bal PWM=40~100%
°
Duty
Ton
Period
------------------- =
rms
p
I
I
2
rms
p
I
I
−
rms
p p
I
I I
−
−
0.5 mA
±