CDK3402 datasheet(7/11 Pages) CADEKA

7 / 11 page

www.cadeka.com

Data Sheet

Current-Setting Resistor - RREF

Full-scale output current of each D/A converter is deter-

mined by the value of the resistor connected between

RREF and GND. Nominal value of RREF is found from:

RREF = 9.1 (VREF/IFS)

where IFS is the full-scale (white) output current (in amps)

from the D/A converter (without sync). Sync is 0.4 * IFS.

D/A full-scale (white) current may also be calculated from:

IFS = VFS/RL

Where VFS is the white voltage level and RL is the total

resistive load (Ω) on each D/A converter. VFS is the blank

to full-scale voltage.

Voltage Reference

All three D/A converters are supplied with a common

voltage reference. Internal bandgap voltage reference

voltage is +1.235V with a 3kΩ source resistance. An

external voltage reference may be connected to the VREF

pin, overriding the internal voltage reference.

A 0.1µF capacitor must be connected between the COMP

pin and VDD to stabilize internal bias circuitry and ensure

low-noise operation.

Voltage Reference Output/Input - VREF

An internal voltage source of +1.235V is output on the

VREF pin. An external +1.235V reference may be applied

here which overrides the internal reference. Decoupling

VREF to GND with a 0.1µF ceramic capacitor is required.

Power and Ground

Required power is a single +5.0V supply. To minimize power

supply induced noise, analog +5V should be connected

to VDD pins with 0.1µF and 0.01µF decoupling capacitors

placed adjacent to each VDD pin or pin pair.

The high slew-rate of digital data makes capacitive cou-

pling to the outputs of any D/A converter a potential

problem. Since the digital signals contain high-frequency

components of the CLK signal, as well as the video out-

put signal, the resulting data feedthrough often looks

like harmonic distortion or reduced signal-to-noise perfor-

mance. All ground pins should be connected to a common

solid ground plane for best performance.

CDK3402 数据表(PDF) 7 Page - Cadeka Microcircuits LLC.

CDK3402 数据表(HTML) 7 Page - Cadeka Microcircuits LLC.

Html Pages

1 2 3 4 5 6 7 8 9 10 11

数据表下载