MCP3465R datasheet(36/110 Pages) MICROCHIP

36 / 110 page

MCP3465R

DS20006414C-page 36

 2020-2021 Microchip Technology Inc.

The possible selections are described in Table 5-1 and

can be set with the MUX[7:0] register bits during the

MUX mode. The MUX[7:4] bits define the selection for

the VIN+ pin (noninverting analog input of the ADC).

The MUX[3:0] bits define the selection for the VIN- pin

(inverting analog input of the ADC).

During Scan mode, the two single-ended input multi-

plexers are automatically set to a certain position,

depending on the Scan sequence and which channel

has been selected by the user. The Scan sequence

channels’ configuration corresponds to a certain code

in the MUX[7:0] register, as defined in Table 5-15.

In order to monitor the Digital Power Supply (DVDD), it

is necessary to connect DVDD externally to one of the

CHn analog inputs, since DVDD is not one of the pos-

sible selections of the analog multiplexer. A similar

setup can be implemented to monitor DGND if DGND is

not connected externally to AGND.

The TEMP Diodes P and M are two internal diodes that

are biased by a current source, and that can be used to

perform a temperature measurement. If TEMP Diode P

is connected to VIN+ and TEMP Diode M to VIN-, then

the ADC output code is a function of the temperature

using Equation 5-1 (see Section 5.1.2, Internal Tem-

perature Sensor for more details). The VCM selection

measures the internal Common-mode voltage source

that biases the Delta-Sigma modulator (this voltage is

not provided at any output of the part).

The possible inputs of the analog multiplexer include,

not only the analog input channels, but also REFIN+/-

inputs, AVDD and AGND, as well as temperature sensor

outputs and the VCM internal Common-mode. This

large selection offers many possibilities for measuring

internal or external data resources of the system and

can serve as diagnostic purposes to increase the

security of the applications. Some monitor channels

are already predefined in Scan mode to further help

users to integrate diagnostics to their applications (for

example, the analog power supply or the temperature

can be constantly monitored in Scan mode; see

Section 5.15.3 “Scan Mode Internal Resource

Channels” for more details of the different resources

that can be monitored in Scan mode).

TABLE 5-1:

ANALOG INPUT MUX DECODING

MUX[7:4] (VIN+) or

MUX[3:0] (VIN-) Code

Selected

Channel

Comment

0000

CH0

0001

CH1

0010

Reserved

Do not use

0011

Reserved

Do not use

0100

Reserved

Do not use

0101

Reserved

Do not use

0110

Reserved

Do not use

0111

Reserved

Do not use

1000

AGND

1001

AVDD

1010

Reserved

Do not use

1011

REFIN+/OUT

1100

REFIN-

1101

TEMP Diode P

1110

TEMP Diode M

1111

Internal VCM

Internal Common-mode voltage for modulator biasing

Note:

When VREF_SEL = 0 (external VREF), and

REFIN+/OUT and REFIN- are selected as

analog inputs for the ADC, the same

REFIN+/OUT and REFIN- pin voltages are

used as the reference for the ADC. This

Diagnostic mode is useful for determining

the full-scale gain error of the ADC when a

gain setting of 1/3x or 1x is used.

MCP3465R Datasheet(PDF) 36 Page - Microchip Technology

MCP3465R Datasheet(HTML) 36 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL