Datasheet
MCP3425
DS22072B-page 14 © 2009 Microchip Technology Inc.
5.2 Configuration Register
The MCP3425 has an 8-bit wide configuration register
to select for: PGA gain, conversion rate, and
conversion mode. This register allows the user to
change the operating condition of the device and check
the status of the device operation. The user can rewrite
the configuration byte any time during the device
operation. Register 5-1 shows the configuration
register bits.
REGISTER 5-1: CONFIGURATION REGISTER
R/W-1 R/W-0 R/W-0 R/W-1 R/W-0 R/W-0 R/W-0 R/W-0
RDY C1 C0 O/C S1 S0 G1 G0
1 * 0 * 0 * 1 * 0 * 0 * 0 * 0 *
bit 7 bit 0
* Default Configuration after Power-On Reset
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 RDY
: Ready Bit
This bit is the data ready flag. In read mode, this bit indicates if the output register has been updated
with a new conversion. In One-Shot Conversion mode, writing this bit to “1” initiates a new conversion.
Reading RDY bit with the read command:
1 = Output register has not been updated.
0 = Output register has been updated with the latest conversion data.
Writing
RDY bit with the write command:
Continuous Conversion mode: No effect
One-Shot Conversion mode:
1 = Initiate a new conversion.
0 = No effect.
bit 6-5 C1-C0: Channel Selection Bits
These are the Channel Selection bits, but not used in the MCP3425 device.
bit 4 O
/C: Conversion Mode Bit
1 = Continuous Conversion Mode. Once this bit is selected, the device performs data conversions
continuously.
0 = One-Shot Conversion Mode. The device performs a single conversion and enters a low power
standby mode until it receives another write/read command.
bit 3-2 S1-S0: Sample Rate Selection Bit
00 = 240 SPS (12 bits),
01 = 60 SPS (14 bits),
10 = 15 SPS (16 bits)
bit 1-0 G1-G0: PGA Gain Selector Bits
00 = 1 V/V,
01 = 2 V/V,
10 = 4 V/V,
11 = 8 V/V