MCP3421DM-WS Microchip Technology, MCP3421DM-WS Datasheet - Page 10

• Manufacturer Part Number: MCP3421DM-WS
• Description: Data Conversion IC Development Tools WT SCALE DEMO BRD 18 I/O 10-BIT ADC
• Manufacturer: Microchip Technology
• Type: ADCr

Specifications of MCP3421DM-WS

• Product: Demonstration Boards
• Tool Is For Evaluation Of: MCP3421
• Interface Type: I2C
• Operating Supply Voltage: 5 V

1.2
FIGURE 1-2:
DS51918A-page 10
ANALOG INPUT CONFIGURATION OPTIONS
The MCP3421 Weight Scale Demo Board has an MCP6V07 auto-zeroed op amp, to
investigate different signal conditioning configuration.
As shown in Figure 1-2, the user can configure the input signal chain with the following
three options, combining the jumpers:
a) Bypassing the MCP6V07: the MCP3421 input pins are directly connected to the
b) Extra gain is added by the low-noise, auto-zeroed op amp MCP6V07, before the
c) PGA = 1x, but uses the MCP6V07 to add high gain. Extra gain is added by the
d) Table 1-1 shows the jumper positions and their results.
Signal Conditioning and ADC on the MCP3421 Weight Scale Demo Board.
sensor output. In this case, the PGA of the MCP3421 is set to a gain of 8. The
jumpers must be set as follows: J4 and J5 are on the left position. J10 and J13
are ON, while J8, J9, J11 and J12 are OFF (see Figure 1-3a).
ADC. The added gain is 50x, and the ADC’s PGA is 2x. For this option the jump-
ers must be set as follows: J4 and J5 are on the right position; J9, J11 and J12
are ON, while J8, J10 and J13 are OFF (see Figure 1-3b).
low-noise, auto-zeroed op amp MCP6V07, before the ADC. The added gain is
250x, and the ADC’s PGA is 1x. For this option the jumpers must be set as fol-
lows: J4 and J5 are on the right position; J8, J11 and J12 are ON, while J9, J10
and J13 are OFF (see Figure 1-3c).
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