MAX1301BEUP+CAL Maxim Integrated, MAX1301BEUP+CAL Datasheet - Page 25

• Manufacturer Part Number: MAX1301BEUP+CAL
• Description: Analog to Digital Converters - ADC Intel R2 Customer special for MAX1301BEUP+
• Manufacturer: Maxim Integrated

Specifications of MAX1301BEUP+CAL

• Number Of Channels: 4/2
• Architecture: SAR
• Conversion Rate: 130 KSPs
• Input Type: Single-Ended/Differential
• Operating Supply Voltage: 4.75 V to 5.25 V
• Maximum Power Dissipation: 879 mW
• Number Of Converters: 1

• External-Acquisition-Mode Control Byte
• Internal-Clock-Mode Control Byte
• Reset Byte
• Partial Power-Down-Mode Control Byte
This prevents the MAX1300/MAX1301 from inadvertent-
ly exiting full power-down mode because of a CS glitch
in a noisy digital environment.
The MAX1300/MAX1301 power up in normal operation
configured for external clock mode with all circuitry
active (Tables 7 and 8). Each analog input channel
(CH0–CH7) is set for single-ended conversions with a
±3 x V
Allow the power supplies to stabilize after power-up. Do
not initiate any conversions until the power supplies
have stabilized. Additionally, allow 10ms for the internal
reference to stabilize when C
= 0.1µF. Larger reference capacitors require longer
stabilization times.
The MAX1300/MAX1301 operate with either an internal or
external reference. The reference voltage impacts the
ADC’s FSR (Figures 12, 13, and 14). An external refer-
ence is recommended if more accuracy is required than
the internal reference provides, and/or multiple converters
require the same reference voltage.
The MAX1300/MAX1301 contain an internal 4.096V
bandgap reference. This bandgap reference is connect-
ed to REFCAP through a nominal 5kΩ resistor (Figure 17).
The voltage at REFCAP is buffered creating 4.096V at
REF. When using the internal reference, bypass
Figure 17. Internal Reference Operation
8- and 4-Channel, ±3 x V
REF
MAX1300
MAX1301
ADC REF
SAR
REFERENCE
bipolar input range (Table 6).
BANDGAP
4.096V
5kΩ
Internal or External Reference
4.096V
______________________________________________________________________________________
1x
REF
= 1.0µF and C
Power-On Reset
Internal Reference
V
REFCAP
RCTH
AGND1
REF
REFCAP
1.0µF
0.1µF
REFCAP with a 0.1µF or greater capacitor to AGND1 and
bypass REF with a 1.0µF or greater capacitor to AGND1.
For external reference operation, disable the internal
reference and reference buffer by connecting REFCAP
to AVDD1. With AVDD1 connected to REFCAP, REF
becomes a high-impedance input and accepts an
external reference voltage. The MAX1300/MAX1301
can accept an external reference voltage of 4.096V or
less. However, to meet all of the electrical characteristic
specifications, V
MAX1301 external reference current varies depending
on the applied reference voltage and the operating
mode (see the External Reference Input Current vs.
External Reference Input Voltage in the Typical
Operating Characteristics ).
Additional samples can be taken and averaged (over-
sampling) to remove the effect of transition noise on
conversion results. The square root of the number of
samples determines the improvement in performance.
For example, with 2/3LSB
noise, 16 (4
the noise to 1LSB
In industrial control applications, 0 to 10V signaling is
common. For 0 to 10V applications, configure the selected
MAX1300/MAX1301 input channel for the single-ended 0
to 3 x V
3 x V
nals saturate at approximately 3 x V
Figure 19 illustrates a simple interface between the
MAX1300/MAX1301 and a 4–20mA signal. 4–20mA sig-
naling can be used as a binary switch (4mA represents
a logic-low signal, 20mA represents a logic-high sig-
nal), or for precision communication where currents
between 4mA and 20mA represent intermediate analog
data. For binary switch applications, connect the
4–20mA signal to the MAX1300/MAX1301 with a resis-
tor to ground. For example, a 250Ω resistor converts
the 4–20mA signal to a 1V to 5V signal. Adjust the
resistor value so the parallel combination of the resistor
and the MAX1300/MAX1301 source impedance is
250Ω. In this application, select the single-ended 0 to
(3 x V
tions that require precision measurements of continu-
ous analog currents between 4mA and 20mA, use a
buffer to prevent the MAX1300/MAX1301 input from
diverting current from the 4–20mA signal.
REF
REF
REF
REF
)/2 range (R[2:0] = 011, Table 6). For applica-
range accommodates 0 to 10V where the sig-
Serial 16-Bit ADCs
Multirange Inputs,
input range (R[2:0] = 110, Table 6). The 0 to
2
= 16) samples must be taken to reduce
Applications Information
Interface with 0 to 10V Signals
Interface with 4–20mA Signals
P-P
REF
.
must be > 38V. The MAX1300/
RMS
(4LSB
REF
Noise Reduction
External Reference
if out of range.
P-P
) transition
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