TDA4857 datasheet(18/56 Pages) PHILIPS

18 / 56 page

2000 Jan 31

Philips Semiconductors

Product speciﬁcation

I2C-bus autosync deﬂection controller for

PC monitors

TDA4857PS

AUTOMATIC VARIATION OF DUTY CYCLE; see Fig.14

tHDRV(OFF)/tH

relative tOFF time of HDRV

output; measured at

VHDRV = 3 V; HDRV duty cycle

is modulated by the relation

IHREF/IVREF

IHDRV =20mA;

fH = 31.45 kHz

IHDRV =20mA;

fH = 58 kHz

45.5

48.5

51.5

IHDRV =20mA;

fH = 110 kHz

X-ray protection: pins XRAY and XSEL

VXRAY(sl)

slicing voltage level for latch

6.22

6.39

6.56

tW(XRAY)(min)

minimum width of trigger pulse

−−

µs

Ri(XRAY)

input resistance at pin 2

VXRAY < 6.38 V + VBE

500

−−

Ω

VXRAY > 6.38 V + VBE

−

Ω

standby mode

−

Ω

XRAYrst

reset of X-ray latch

pin 9 open-circuit or

connected to GND

set control bit SOFTST via

the I2C-bus

−

pin 9 connected to VCC via

RXSEL

switch off VCC then

re-apply VCC

−

VCC(XRAY)(min)

minimum supply voltage for

correct function of the X-ray

latch

pin 9 connected to VCC via

RXSEL

−−

VCC(XRAY)(max)

maximum supply voltage for

reset of the X-ray latch

pin 9 connected to VCC via

RXSEL

−−

RXSEL

external resistor at pin 9

no reset via I2C-bus

−

130

Ω

Vertical oscillator [oscillator frequency in application without adjustment of free-running frequency ffr(V)]

ffr(V)

free-running frequency

RVREF =22kΩ;

CVCAP = 100 nF

43.3

fcr(V)

vertical frequency catching

range

constant amplitude; note 7 50

−

160

VVREF

voltage at reference input for

vertical oscillator

−

3.0

−

td(scan)

delay between trigger pulse

and start of ramp at VCAP

(pin 24) (width of vertical

blanking pulse)

control bit VBLK = 0

220

260

300

µs

control bit VBLK = 1

305

350

395

µs

IVAGC

amplitude control current

control bit AGCDIS = 0

±120

±200

±300

µA

control bit AGCDIS = 1

−

−µA

CVAGC

external capacitor at VAGC

(pin 22)

150

−

220

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT

TDA4857 Datasheet(PDF) 18 Page - NXP Semiconductors

TDA4857 Datasheet(HTML) 18 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

Datasheet Download

Link URL