MAX1303BEUP+ Maxim Integrated Products, MAX1303BEUP+ Datasheet - Page 21

• Manufacturer Part Number: MAX1303BEUP+
• Description: ADC Single SAR 115KSPS 16-Bit Serial 20-Pin TSSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX1303BEUP+

• Package: 20TSSOP
• Resolution: 16 Bit
• Sampling Rate: 115 KSPS
• Architecture: SAR
• Number Of Adcs: 1
• Number Of Analog Inputs: 4|2
• Digital Interface Type: Serial (SPI, QSPI, Microwire)
• Input Type: Voltage
• Signal To Noise Ratio: 90(Typ) dB
• Polarity Of Input Voltage: Unipolar|Bipolar

Figure 9. Common-Mode Voltage vs. Input Voltage (FSR = V
Figure 11. Common-Mode Voltage vs. Input Voltage (FSR = 4 x
V
Communication with the MAX1302/MAX1303 is accom-
plished using the three input data word formats shown
in Table 3. Each input data word begins with a start bit.
The start bit is defined as the first high bit clocked into
DIN with CS low when any of the following are true:
• Data conversion is not in process and all data from
• The device is configured for operation in external
• The device is configured for operation in external
• The device is configured for operation in internal
REF
the previous conversion has clocked out of DOUT.
clock mode (mode 0) and previous conversion-result
bits B15–B3 have clocked out of DOUT.
acquisition mode (mode 1) and previous conversion-
result bits B15–B7 have clocked out of DOUT.
clock mode, (mode 2) and previous conversion-
result bits B15–B4 have clocked out of DOUT.
)
-2
-4
-6
-2
-4
-6
6
4
2
0
6
4
2
0
-8
-8
______________________________________________________________________________________
-6
-6
8-/4-Channel, ±V
-4
-4
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
-2
-2
0
0
2
2
V
V
REF
REF
4
4
= 4.096V
= 4.096V
6
6
8
8
Start Bit
REF
)
Output data is clocked out of DOUT in offset binary for-
mat on the falling edge of SCLK, MSB first (B15). For
output binary codes, see the Transfer Function section
and Figures 12, 13, and 14.
Each analog input has two configurable parameters:
• Single-ended or true-differential input
• Input voltage range
These parameters are configured using the analog input
configuration byte as shown in Table 2. Each analog
input has a dedicated register to store its input configura-
tion information. The timing diagram of Figure 15 shows
how to write to the analog input configuration registers.
Figure 16 shows DOUT and SSTRB timing.
An ADC’s transfer function defines the relationship
between the analog input voltage and the digital output
code. Figures 12, 13, and 14 show the MAX1302/
MAX1303 transfer functions. The transfer function is
determined by the following characteristics:
• Analog input voltage range
• Single-ended or differential configuration
• Reference voltage
The axes of an ADC transfer function are typically in least
significant bits (LSBs). For the MAX1302/MAX1303, an
LSB is calculated using the following equation:
where N is the number of bits (N = 16) and FSR is the
full-scale range (see Figures 7 and 8).
Figure 10. Common-Mode Voltage vs. Input Voltage (FSR = 2 x
V
REF
REF
)
Serial 16-Bit ADCs
Multirange Inputs,
-2
-4
-6
6
4
2
0
1
-8
LSB
-6
=
-4
INPUT VOLTAGE (V)
2
FSR
-2
N
Configuring Analog Inputs
×
0
×
4 096
Transfer Function
.
2
V
Output Data Format
REF
V
REF
4
V
= 4.096V
6
8
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