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Mode control – Rainbow Electronics MAX1301 User Manual

Page 22

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MAX1300/MAX1301

Mode Control

The MAX1300/MAX1301 contain one byte-wide mode-
control register. The timing diagram of Figure 15 shows
how to use the mode-control byte, and the mode-con-
trol byte format is shown in Table 7. The mode-control
byte is used to select the conversion method and to
control the power modes of the MAX1300/MAX1301.

Selecting the Conversion Method

The conversion method is selected using the mode-con-
trol byte (see the Mode Control section), and the conver-
sion is initiated using a conversion-start command (Table
3, and Figures 2, 3, and 4).The MAX1300/MAX1301 con-
vert analog signals to digital data using one of three
methods:

External Clock Mode, Mode 0 (Figure 2)

• Highest maximum throughput (see the Electrical

Characteristics table)

• User controls the sample instant

• CS remains low during the conversion

• User supplies SCLK throughout the ADC con-

version and reads data at DOUT

External Acquisition Mode, Mode 1 (Figure 3)

• Lowest maximum throughput (see the Electrical

Characteristics table)

• User controls the sample instant

• User supplies two bytes of SCLK, then drives

CS high to relieve processor load while the ADC
converts

• After SSTRB transitions high, the user supplies

two bytes of SCLK and reads data at DOUT

Internal Clock Mode, Mode 2 (Figure 4)

• High maximum throughput (see the Electrical

Characteristics table)

• The internal clock controls the sampling instant

8-/4-Channel, ±12V Multirange Inputs,
Serial 16-Bit ADCs

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1 LSB = FSR x V

REF

65,536 x 4.096V

BINARY OUTPUT CODE (LSB [hex])

FFFF

FFFE

FFFD

8001

8000

7FFF

0003

0002

0001

0000

FSR

0

1

2

3

32,768

65,533 65,535

INPUT VOLTAGE (LSB [DECIMAL])

(AGND1)

FSR

Figure 13. Ideal Unipolar Transfer Function, Single-Ended
Input, -FSR to 0

1 LSB = FSR x V

REF

65,536 x 4.096V

BINARY OUTPUT CODE (LSB [hex])

FFFF

FFFE

FFFD

8001

8000

7FFF

0003

0002

0001

0000

FSR

0

1

2

3

32,768

65,533 65,535

INPUT VOLTAGE (LSB [DECIMAL])

(AGND1)

FSR

Figure 14. Ideal Unipolar Transfer Function, Single-Ended
Input, 0 to +FSR

1 LSB = FSR x V

REF

65,536 x 4.096V

BINARY OUTPUT CODE (LSB [hex])

FFFF

FFFE

FFFD

8001

8000

7FFF

0003

0002

0001

0000

FSR

-32,768 -32,766

0

+32,765 +32,767

INPUT VOLTAGE (LSB [DECIMAL])

AGND1 (DIF/SGL = 0)

OV (DIF/SGL = 1)

FSR

-1

+1

Figure 12. Ideal Bipolar Transfer Function, Single-Ended or
Differential Input