LH1684F View Datasheet(PDF) - Sharp Electronics
Part Name
Description
MFG CO.
'LH1684F' PDF : 34 Pages View PDF
LH1684F
20
6.6 Precautions
(1) Setting of external voltage of Vbl and Vb2 pins
The LHl684Fdoes not have the biasvoltage setting circuit forthe output operational amplifiers
and the output buffers. Therefore it is necessary to input the suitable voltage to Vbl pin and
Vb2 pin.
Set the voltage value to an optimum value in the range of Vcc to GND as shown in the diagram
below, fully evaluating the current consumption, picture quality, etc.
(Example of biascircuit)
t----r>
Vbl, Vb2
Set the resistance to Rl +R2=50 kfI
(2) Setting of Input pins
Since 6 pins of SP, CK, CTR, MODE, Vbl , and Vb2 of the input pins are not pulled up or
pulled down in the LSI, never use these 6 pins in the “OPEN” condition.
Since VA, VB, and VC pins are for inputting video signals, necessary video signals must be
input always.
Except VA, VB, VC, Vbl , Vb2, SP, CK, CTR, and MODE, all other input pins are pulled up or
pulled down in the LSI. However,because of preventing malfunction due to noise, etc., avoid
using the “OPEN” condition whenever possible, and set to “H” level or “L”level.
(3) Input video signals
Input video signalsaretarget for analog signals(continuous signals).
The input band of video signals is applicable up to the maximumof 10 MHz.
(4) Bypass capacitor
lfthe noise of alogicsystem is superposed on analog circuits such asthe sampleand hold
circuits, analog characteristics (such as output voltage deviation and dynamic range,etc.) may
deteriorate. Forthis reason, insert bypass capacits or of about 1 pF between VCC and GND.
Fully evaluate and determine the value of bypass capacits orwith actually mounted on the
LCD panel.
L
Share Link: 
