AD9849 datasheet(32/36 Pages) AD

32 / 36 page

REV. 0

AD9848/AD9849

–32–

Driving the CLI Input

The AD9848/AD9849’s master clock input (CLI) may be

used in two different configurations, depending on the appli-

cation. Figure 23a shows a typical dc-coupled input from the

master clock source. When the dc-coupled technique is used,

the master clock signal should be at standard 3 V CMOS

logic levels. As shown in Figure 23b, a 1000 pF ac-coupling

capacitor may be used between the clock source and the CLI

input. In this configuration, the CLI input will self-bias to

the proper dc voltage level of approximately 1.4 V. When the

ac-coupled technique is used, the master clock signal can be

as low as

± 500 mV in amplitude.

CCD IMAGER

SIGNAL

OUT

AD9848/AD9849

CCDIN

Figure 22a. CCD Connections (2 H-Clock)

CCD IMAGER

SIGNAL

OUT

AD9848/AD9849

CCDIN

Figure 22b. CCD Connections (4 H-Clock)

CLI

MASTER CLOCK

AD9848/AD9849

ASIC

Figure 23a. CLI Connection, DC-Coupled

CLI

MASTER CLOCK

AD9848/AD9849

ASIC

LPF

1nF

Figure 23b. CLI Connection, AC-Coupled

Internal Mode Circuit Configuration

The AD9848/AD9849 may be used in Internal Mode using

the circuit configuration of Figure 24. Internal Mode uses the

same circuit as Figure 21, except that the horizontal pulses

(CLPOB, CLPDM, PBLK, and HBLK) are internally gener-

ated in the AD9848/AD9849. These pins may be grounded when

Internal Mode is used. Only the HD and VD signals are required

from the ASIC.

HD/VD

INPUTS

AD9848/AD9849

Figure 24. Internal Mode Circuit Configuration

AD9849 датащи(PDF) 32 Page - Analog Devices

AD9849 датащи(HTML) 32 Page - Analog Devices

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

датащи скачать

ссылки URL