MAX1231EVKIT Maxim Integrated Products, MAX1231EVKIT Datasheet - Page 5

• Manufacturer Part Number: MAX1231EVKIT
• Description: EVAL KIT FOR MAX1231
• Manufacturer: Maxim Integrated Products

Specifications of MAX1231EVKIT

• Number Of Adc's: 1
• Number Of Bits: 12
• Sampling Rate (per Second): 300k
• Data Interface: Serial
• Inputs Per Adc: 16 Single Ended or 8 Differential
• Input Range: ±VREF/2
• Power (typ) @ Conditions: 1.86mW @ 300kSPS
• Voltage Supply Source: Single Supply
• Operating Temperature: 0°C ~ 70°C
• Utilized Ic / Part: MAX1231
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Because the most significant bits are aligned, the mea-
surement code numbers reported by the software are
four times the actual measurement code number.
Reconstructed voltage values are unaffected. Adjust
the graph window by selecting its Options menu; set
its Sub-LSBs to 2.
The MAX1230 is the 5V version of the MAX1231. To
evaluate the MAX1230, request a free sample of the
MAX1230BCEG. Replace U1 with a MAX1230, and
move the shunt to the 5V position. In the software’s
Options menu, select Reference = 4.096V.
An external reference can be applied in single-ended or
differential mode. In differential mode, analog input pin
AIN14 is used as the REF(-) return connection. In single-
ended mode, the reference returns to common ground.
With the power off, connect the external reference. Then
power up the system and run the evaluation software.
Under Setup, select the appropriate reference input con-
figuration. If using a single-ended reference, set
Reference Input to 01xx01xx pin15 = AIN14. If using a
differential reference, set Reference Input to 01xx11xx
pin 15 = REF-.
Table 2. Jumper JU1 (V
Selection)
*Indicates default configuration.
POSITION
SHUNT
Open
2–3*
1–2
MAX1231 Evaluation Kit/Evaluation System
Unspecified
V
_______________________________________________________________________________________
DD
Using an External Reference
5V
3V
(V)
Evaluating the MAX1230
Normal operation with U1 =
MAX1230 or MAX1030.
Normal operation with U1 =
MAX1231 or MAX1031.
D o not op erate ki t w i th JU 1 op en.
DD
Voltage
FUNCTION
Problem: No output measurement. System seems to
report zero voltage or fails to make a measurement.
Solution: Check V
ence voltage using a digital voltmeter. Use an oscillo-
scope to verify that the conversion-start signal is being
strobed.
Problem: Measurements are erratic, unstable, or have
poor accuracy.
Solution: Check the reference voltage using a digital
voltmeter. Use an oscilloscope to check for noise.
When probing for noise, keep the oscilloscope ground
return lead as short as possible, preferably less than
0.5in (10mm).
Problem: Unacceptable errors occur when measuring
a transducer.
Solution: Although most signal sources can be con-
nected directly to the MAX1231’s analog inputs, some
high-impedance signal sources can require an input
buffer. Check for settling errors by increasing the
acquisition time (internal clock mode 01). If necessary,
use a MAX4430 to buffer high-impedance signal
sources.
Table 3. Optional Jumper JU2 (AIN15
Alternate Function)
*Indicates default configuration.
(default trace
JU2 STATE
on PCB)
Closed*
Open
Connected to µC
module J1 pin 29
(through level
shifter)
Connected to TB5
pin 4
CONNECTION
U1 PIN 16
DD
supply voltage. Check the refer-
U1 pin 16 = CNVST
conversion start
command. Leave TB5
pin 4 unconnected.
U1 pin 16 = AIN15
analog input. Connect
signal source to terminal
block TB5 pin 4.
Troubleshooting
FUNCTION
5