ver.0.1 NJM2274A -1- low power video amplifier with y-c mixer general description package outline the NJM2274A is low voltage operation video amplifier with y/c mixer and 75-ohm driver. the NJM2274A is suitable for dsc, dvc, ccd camera and other portable video applications. the njm2274 is 0.5vp-p input, and the NJM2274A is 1.0vp-p input. features low operating voltage 2.8 to 5.5v y/c mix circuit 6db amplifier, 75 ? driver circuit y-input: clamp c-input: bias bipolar technology package outline vsp8 pin configuration block diaglam NJM2274Ar 1 2 3 4 8 7 6 5 1: yin 2: gnd 3: vout 4: vsag 5: v + 6: power save 7: c mute 8: cin yin cin vsag vout 75 ? dr iv er bias cla mp 6db 1 8 3 4 7 2 6 5 v+ power save c mute gnd
NJM2274A - 2 - abosolute maximum ratings (ta=25 c) paramrter symbol ratings unit supply voltage v + 7.0 v power dissipation p d 580(note1) mw operating temperature range topr -40 to +85 c storage temperature range tstg -40 to +125 c (note) at on a board of eia/jedec specification. (114.3 x 76.2 x 1.6mm 2 layers, fr-4) recommended opearating condition (ta=25 c) parameter symbol test condition min. typ. max. unit operating voltage vopr 2.8 3.0 5.5 v electrical characteristics ( v + =3.0v,ta=25 c) parameter symbol test condition min. typ. max. unit operating current icc no signal - 9.3 14.0 ma operating current (power save mode) isave power save mode - 0.8 1.4 ma maximum output voltage vom f=1khz,thd=1% 2.2 - - vpp voltage gain gv yin=100khz, 1.0vpp, sine video signal (note) 5.9 6.4 6.9 db frequency characteristic gf yin=10mhz/100khz, 1.0vpp, sine video signal (note) -1.0 0 +1.0 db differential gain dg yin=1.0vpp, 10step video signal - 2.5 - % differential phase dp yin=1.0vpp, 10step video signal - 1.0 - deg chroma mute cross talk ct cin=4.43mhz, 0.2vpp - -65 - db s/n ratio snv yin=0.2vpp, 100%white video signal, cin=ac gnd wide band 100khz to 6mhz,r l =75ohm - 66 - db second distortion hv yin=0.2vpp, 3.58mhz red field video signal, cin=ac gnd r l =75ohm - -40 - db input resistance rcin chroma signal input - 20 - k ? vthmh 1.4 - v + mute switch change voltage vthml 0 - 0.6 v vthph 1.4 - v + power save switch change voltage vthpl 0 - 0.6 v note) sine video signal 714mvpp 286mvpp 40us NJM2274A -3- control terminal explanation parameter status note h chroma mute: on l chroma mute: off chroma mute open chroma mute: off h power save: off (active) l power save: on (mute) power save open power save: on (mute) test circuit 75 ? 75 ? p.s ctl 100f 22f 876 3 2 1 5 4 1000pf vout1 NJM2274A ps ctl vout gnd vsag yin v + cin cmute ctl 0.1f 75 ? 50 ? yin vout2 75 ? 50 ? cin 0.1f 100pf 100pf 10f v + cmute ctl + +
NJM2274A - 4 - application circuit (1) standard circuit (2) sag correction unused circuit (1) standard circuit the sag correction reduces output coupling capacitor values. adjust the c1 value, checking the waveform containing a lot of low frequency components like a bounce waveform (in case of worst condition). change the capacitor of c1 into a large value to improve sag . (2) sag correction unused circuit cancel the sag correction to improve lost synchronization. connect the coupling capacitor after connecting the vout pin and vsag pin. the recommended value is 470f or more. (note) the NJM2274A can?t drive two-line load of 150 ? . 75 ? p.s ctl 100f 22f 876 3 2 1 5 4 1000pf vout NJM2274A ps ctl vout gnd vsag yin v + cin cmute ctl 0.1f 75 ? yin 75 ? cin 0.1f 10f v + cmute ctl + + c1 p.s ctl 876 3 2 1 5 4 1000pf NJM2274A ps ctl vout gnd vsag yin v + cin cmute ctl 0.1f 75 ? yin 75 ? cin 0.1f 10f v + cmute ctl 75 ? 470f + c1 vout
NJM2274A -5- terminal description pin no. symbol function voltage equivalent circuit 1 yin luminance signal input 1.3v 2 gnd gnd 0v 3 vout composite video signal output 0.3v 4 vsag sag correction 0.38 400 400 1 vcc 6.4k 750 3 vcc 6.4k 750 4 vcc
NJM2274A - 6 - pin no. symbol function voltage equivalent circuit 5 v+ power supply - 6 power save ctl. power save control 0v 7 cmute ctl chroma signal mute control 0v 8 cin chroma signal input 1.4v 6 12k 36k 7 12k 36k 20k 400 8 vcc
NJM2274A -7- application this ic requires 1m ? resistance between yin pin and gnd for clamp type input since the minute current causes an unstable pin voltage. [caution] the specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. the application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights.
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