MCP3909EV-MCU16 Microchip Technology, MCP3909EV-MCU16 Datasheet - Page 12

• Manufacturer Part Number: MCP3909EV-MCU16
• Description: EVALUATION BOARD FOR MCP3909
• Manufacturer: Microchip Technology

Specifications of MCP3909EV-MCU16

• Number Of Adc's: 2
• Number Of Bits: 16
• Sampling Rate (per Second): 15k
• Data Interface: Serial
• Inputs Per Adc: 1 Differential
• Input Range: ±1 V
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Utilized Ic / Part: MCP3909
• Silicon Manufacturer: Microchip
• Application Sub Type: ADC
• Kit Application Type: Data Converter
• Silicon Core Number: MCP3909
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

MCP3909 ADC Evaluation Board for 16-Bit MCUs User’s Guide
1.3
DS51777A-page 8
MCP3909 DELTA-SIGMA SAMPLING / MCLK OPTIONS
The MCP3909 device is an ADC with a second order modulator and a third order sinc
filter. This Delta-Sigma A/D converter has an oversampling ratio of 64. The CLKIN pin
of the MCP3909 is the oversampling clock (MCLK) input and the output data rate is
MCLK/256. The MCP3909 ADC Evaluation Board for 16-Bit MCUs offers two different
options for the MCP3909 master clock (MCLK).
1.3.1
The MCP3909 ADC Evaluation Board for 16-Bit MCUs is populated with a 3.58 MHz
crystal, being used as a clock source by placing jumpers in the following position on the
MCP3909 Digital I/O header block:
FIGURE 1-3:
1.3.2
The PIC MCU can be used to generate the CLKIN (MCLK) signal for the MCP3909,
setting the ADC sample rate through the use of the output compare module OC1. To
use this, make the following jumper change to the MCP3909 Digital I/O header block:
FIGURE 1-4:
The frequency of the OC1 output is based on the PR1 bits settings in the firmware
(for both PIC24 and dsPIC33 PIM modules supplied with this system). These settings
can be cycled through by pressing SW2 of the PIM AUX Switches. The Table 1-1
shows the settings that are immediately available by changing PR2, the timer period
register:
TABLE 1-1:
Gear
1
2
3
4
5
Using the Crystal X2
Driving the clock with the PIM module
CLKOUT
CLKOUT
CLKIN
CLKIN
CLKIN
CLKIN
SAMPLE RATES
PR Bit Setting
ADC Clock Selection Jumpers - External Crystal.
ADC Clock Selection Jumpers - Clock from MCU.
48
14
8
4
2
XTAL
XTAL
XTAL
XTAL
PIM OC1
PIM OC1
OC1 Frequency
1264.36 kHz
2.2755 MHz
3.7921 MHz
164.96 kHz
758.7 kHz
© 2008 Microchip Technology Inc.
MCP3909 Data Rate
14.81 ksps
644.2 sps
2.96 ksps
4.94 ksps
8.89 ksps