Daewoo 21Q4, 21Q2, 21Q1, 14T2, 14Q2, 20Q1 Name Description, Vertical Guard, Beam current limitinq

No	Name	Description
		A voltage detection circuit is connected to both pins.
		- pin12 if V12 <6.8V than a power on reset, POR, is generated. The Hout
		output is disabled immediate.
		- pin37 if V37 <5.8V than the horizontal output is disabled immediate.
13	INT CVBS INPUT	It is recommended that the CVBS1 int and CVBS2 ext input amplitudes are
17	EXT CVBS INPUT	1 Vpp (inclusive sync amplitude).
		This, because the noise detector switches the 1 loop to slow mode
		(i.e. auto	1mode when FOA, FOB = 0,0) when noise level exceeds
		100mVrms (i.e. at S/N of 20dB).
14	GROUND	All internal circuits are connected to this ground pin 14.
15	AUDIO OUTPUT	The output signal is volume controlled and is active for both internal and
		external audio signals. The nominal gain is +9dB and -71dB, which gives
		a total control range of 80dB.
		The output signal range therefor is 0.14- 1400mVrms
		The bandwidth is >100kHz, the DC level is 3.3V and the output impedance
		is 250 .
16	DECOUPLING	Voltage variations at pin 16, which can be due to external leakage current or
	FILTER TUNING	crosstalk from interference sources, should be less than 50mV to ensure that
		tuning of filters/delay cells remains correct.
18	BLACK CURRENT	For correct operation of the loop CURRENT information is supplied to the
	INPUT	black current input pin.
19	BLUE OUTPUT	The RGB outputs are supplied to the video output stages from pins 21, 20
20	GREEN OUTPUT	and 19 respectively.
21	RED OUTPUT	For nominal signals (i.e. CVBS/S-VHS, -(R-Y)/- (R-Y), TXT inputs) and for
		nominal control settings, then the RGB output Signal amplitudes is
		typically 2VBLACK_WHITE.
22	V-GUARD INPUT/	Vertical Guard
	BEAM CURRENT	With this function, the correct working of the vertical deflection can be
	LIMITER	monitored. If the vertical deflection fails, the RGB outputs are blanked to
		prevent damage to the picture tube.
		Beam current limitinq
		The beam current limiting function is realised by reducing the contrast (and
		finally the brightness) when the beam current reaches s too high level. The
		circuit falls apart in two functions:
		- Average beam current limiting (ABL): reacting on the average content of
		the picture
		- Peak white limiting (PWL): reacting on high local peaks in the RGB signal.
23	RED INPUT	The Rin, Gin, Bin input signals (nominal signal amplitude of 700mV) are
24	GREEN INPUT	AC coupled to pin 23, 24 and 25 respectively.
25	BLUE INPUT	Clamping action occurs during burstkey period.
26	RGB INSERTION	The table below a survey is given of the three modes which can be selected
	SWITCH INPUT	with a voltage on RGB insertion switch input pin ;
		Vpin26	I2C function	Selected RGB signal
		0.9V-3V	IE1=0	RGB(internal)
			IE1=1	Rin,Gin,Bin
				(fast insertion on pin23,24,25)
		> 4V	IE1=X	OSD can be inserted at the RGBout pins
27	LUMINANCE INPUT	An nominal input signal amplitude of 1 Vblack-white MUST be DC coupled

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