MP7226 查看數據表（PDF） - Exar Corporation

零件编号

产品描述 (功能)

生产厂家

MP7226

BiCMOS Fixed, Quad, Voltage Output, Single or Dual Supply 8-Bit Digital-to-Analog Converter

Exar Corporation 

APPLICATIONS INFORMATION

Power On Reset

At power up, all inputs are reset to 0 V if WR = 1. For WR = 0,

the addressed DAC will receive input data.

Power Supply

The MP7226 can operate with either a single or dual power

supply. Improved zero-code settling error can be obtained by

using dual power supplies. The dual power supply specifica-

tions are a positive supply (VDD) range of +10.5V to +16.5V, and

a –5V supply (VSS) . The single power supply specifications are

a positive supply (VDD) range of +10.5V to +16.5V, or range of

+4.75V to 5.5V . The specified reference voltage (VREF) range

under these conditions is from +2V to VDD –4V. For those appli-

cations requiring +10V at the output (VREF = +10V), VDD must

be +14V minimum to meet data sheet limits . 8-bit performance

is guaranteed for single supply operation (VSS = 0V); however,

zero code output sink capability is improved with VSS = –5V. For

adequate DAC and Buffer operation, VREF must always be be-

low VDD by at least 3.5V.

Power Supply Decoupling

The Power Supplies used with the MP7226 should be well

regulated and filtered. Local power supply decoupling consist-

ing of a 10µF tantalum capacitor in parallel with a 0.01µF ce-

ramic is recommended. The decoupling capacitors should be

connected between the VDD and AGND, and between VSS and

AGND if VSS = –5V.

Unipolar Output Operation

In this configuration, the reference voltage is the same polar-

ity as the output voltage. Since the reference voltage must al-

ways be positive with respect to GND, the output can only be 0 or

positive.

Table 2. shows the code relationship for the part in unipolar

operation

MP7226

Digital Input

11111111

10000001

10000000

01111111

00000001

00000000

Analog Output, VOUT

) VREFĂ (225556)

) VREFĂ (122596)

)

VREFĂ

(122586)

+

)

VREF

2

) VREFĂ (122576)

) VREFĂ (2156)

0Ă V

Note

:

1Ă

LSB

+

(2*8)Ă

(VREF)

+

1

256

Ă

(VREF)

Table 2. Unipolar Code Table

Digital Input

11111111

10000001

10000000

01111111

00000001

00000000

Analog Output

) VREFĂ (112278)

) VREFĂ (1128)

0V

* VREFĂ (1128)

* VREFĂ (112278)

* VREFĂ (112288) +Ă * VREF

Table 3. Bipolar Code Table

Rev. 2.00

9

Share Link: