AD7228KRZ datasheet(11/16 Pages) AD

номер детали	AD7228KRZ

подробное описание детали	LC2MOS Octal 8-Bit DAC

Download	16 Pages

Scroll/Zoom	100%

производитель	AD [Analog Devices]

домашняя страница	http://www.analog.com

Logo

11 / 16 page

AD7228

Data Sheet

Rev. D | Page 10 of 15

Table 7. Unipolar Code Table

DAC Latch Contents

MSB

LSB1

Analog Output

1 1 1 1

+VREF(255/256)

1 0 0 0

0 0 0 1

+VREF(129/256)

1 0 0 0

0 0 0 0

+VREF

2

256

128

REF

V

+

=













0 1 1 1

1 1 1 1

+VREF(127/256)

0 0 0 0

0 0 0 1

+VREF(1/256)

0 0 0 0

0 V

1

1 LSB = (VREF)(2−8) = VREF (1/256).

Bipolar Output Operation

Each of the DACs on the AD7228 can be individually configured

for bipolar output operation. This is possible using one external

amplifier and two resistors per channel. Figure 11 shows a circuit

used to implement offset binary coding (bipolar operation) with

DAC 1 of the AD7228. In this case,

)

(

)

(

1

REF

OUT

V

R1

R2

V

D

R1

R2

V

×













−

×











 +

=

With R1 = R2,

VOUT = (2D1 − 1) × (VREF)

where D1 is a fractional representation of the digital word in

Latch 1 of the AD7228 (0 ≤ D1 ≤ 255/256).

Table 8. Bipolar Code Table

DAC Latch Contents

MSB

LSB

Analog Output

1 1 1 1

+VREF(127/128)

1 0 0 0

0 0 0 1

+VREF(1/128)

1 0 0 0

0 0 0 0

0 V

0 1 1 1

1 1 1 1

−VREF(1/128)

0 0 0 0

0 0 0 1

−VREF(127/128)

0 0 0 0

−VREF(128/128) = −VREF

Mismatch between R1 and R2 causes gain and offset errors;

therefore, these resistors must match and track over temperature.

The AD7228 can be operated from a single supply or from dual

supplies. Table 8 shows the digital code vs. output voltage

relationship for the circuit of Figure 11 with R1 = R2.

AC Reference Signal

In some applications, it may be desirable to have an ac signal

applied as the reference input to the AD7228. The AD7228 has

multiplying capability within the upper (10 V) and lower (2 V)

limits of reference voltage when operated with dual supplies.

Therefore, ac signals must be ac-coupled and biased up before

being applied to the reference input. Figure 12 shows an ac

signal applied to the reference input of the AD7228. For input

frequencies up to 50 kHz, the output distortion typically remains

less than 0.1%. The typical 3 dB bandwidth for small signal

inputs is 800 kHz.

12

9

11

1

GND

*ADDITIONAL PINS OMITTED FOR CLARITY.

VSS

VDD

VOUT

VOUT1

R1

10kΩ

±0.1%

R2

10kΩ

±0.1%

+15V

–15V

VREF

AD7228*

VREF

10

DAC 1

Figure 11. Bipolar Output Circuit

+10V

REFERENCE

INPUT

15kΩ

+15V

–5V

10kΩ

+2V

12

9

11

1

GND

*ADDITIONAL PINS OMITTED FOR CLARITY.

VSS

VDD

VOUT1

VREF

+15V

AD7228*

10

DAC 1

+4V

–4V

Figure 12. Applying an AC Signal to the AD7228

Аналогичный номер детали - AD7228KRZ

производитель	номер детали	датащи	подробное описание детали
Analog Devices	AD7228KR	210Kb / 8P	LC2MOS Octal 8-Bit DAC REV. A

More results

Аналогичное описание - AD7228KRZ

производитель	номер детали	датащи	подробное описание детали
Analog Devices	AD7228UQ	169Kb / 8P	LC2MOS Octal 8-Bit DAC REV. A
	AD7228KN	210Kb / 8P	LC2MOS Octal 8-Bit DAC REV. A
	AD7228UQ	169Kb / 8P	LC2MOS Octal 8-Bit DAC REV. A
	AD7228KR	210Kb / 8P	LC2MOS Octal 8-Bit DAC REV. A
	AD7228BQ	169Kb / 8P	LC2MOS Octal 8-Bit DAC REV. A
	AD7228LP	169Kb / 8P	LC2MOS Octal 8-Bit DAC REV. A
	AD7228A	210Kb / 8P	LC2MOS Octal 8-Bit DAC Mount Packages REV. A
	AD7568BPZ	354Kb / 14P	LC2MOS Octal 12-Bit DAC REV. C
	AD7568	241Kb / 12P	LC2MOS Octal 12-Bit DAC REV. B
	AD7568BSZ	354Kb / 14P	LC2MOS Octal 12-Bit DAC REV. C

More results

AD7228KRZ датащи(PDF) 11 Page - Analog Devices

AD7228KRZ датащи(HTML) 11 Page - Analog Devices

Аналогичный номер детали - AD7228KRZ

Аналогичное описание - AD7228KRZ

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

датащи скачать

ссылки URL