BT856 datasheet(43/54 Pages) ETC

43 / 54 page

Brooktree®

PC BOARD CONSIDERATIONS

Applications Information

Bt856/7

Applications Information

ESD and Latchup

Considerations

Correct ESD-sensitive handling procedures are required to prevent device damage.

Device damage can produce symptoms of catastrophic failure or erratic device be-

havior with leaky inputs.

All logic inputs should be held low until power to the device has settled to the

speciﬁed tolerance. DAC power decoupling networks with large time constants

should be avoided; they could delay VAA power to the device. Ferrite beads must

be used only for analog power VAA decoupling. Inductors cause a time constant

delay that induces latchup.

Latchup can be prevented by ensuring that all VAA and GND pins are at the

same potential and that the VAA supply voltage is applied before the signal pin

voltages. The correct power-up sequence ensures that any signal pin voltage will

never exceed the power supply voltage.

Sync and Burst Timing

Table 9 lists the resolutions and clock rates for the various modes of operation.

Table 10 lists the horizontal counter values for the end of horizontal sync, start

of color burst, end of color burst, and the ﬁrst active pixel for the various modes of

operation. The front porch is the interval before the next expected falling HSYNC*

when outputs are automatically blanked.

The horizontal sync width is measured between the 50% points of the falling

and rising edges of horizontal sync.

The start of color burst is measured between the 50% point of the falling edge

of horizontal sync and the ﬁrst 50% point of the color burst amplitude (nominally

+20 IRE for NTSC/PAL–M and 150 mV for PAL–B, D, G, H, I, N, N-Argentina

above the blanking level).

The end of color burst is measured between the 50% point of the falling edge of

horizontal sync and the last 50% point of the color burst envelope (nominally +20

IRE for NTSC/PAL–M and 150 mV for PAL–B, D, G, H, I, N, N-Argentina above

the blanking level).

Table 9. Field Resolutions and Clock Rates for Various Modes of Operation

Operating Mode

Active Resolution

(pixels)

Total Resolution

(pixels)

CLKX1 Frequency

(MHz)

NTSC/PAL–M CCIR601

PAL–B, D, G, H, I, N, N–Argentina CCIR601

NTSC Square PIXEL (Note 1)

PAL–B, D, G, H, I, N, N–Argentina SQUARE

PIXEL (Note 1)

720 x 240

720 x 288

640 x 240

768 x 288

858 x 262

864 x 312

780 x 262

944 x 312

13.5000

12.2727

14.7500

Note 1: PAL–M and PAL–N (Argentina) not available in square pixel format.

BT856 Datasheet(PDF) 43 Page - List of Unclassifed Manufacturers

BT856 Datasheet(HTML) 43 Page - List of Unclassifed Manufacturers

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

Datasheet Download

Link URL