MCP3423-E/MF Microchip Technology, MCP3423-E/MF Datasheet - Page 31

• Manufacturer Part Number: MCP3423-E/MF
• Description: IC ADC 18BIT 3.75SPS 2CH 10-DFN
• Manufacturer: Microchip Technology

Specifications of MCP3423-E/MF

• Data Interface: I²C, Serial
• Number Of Bits: 18
• Sampling Rate (per Second): 3.75
• Number Of Converters: 1
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 10-DFN
• Resolution (bits): 18bit
• Sampling Rate: 3.75SPS
• Input Channel Type: Differential
• Supply Voltage Range - Analog: 2.7V To 5.5V
• Supply Current: 145µA
• Digital Ic Case Style: DFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: MCP3423EV - BOARD EVAL 18BIT 2CH ADC MCP3423
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

6.0
The MCP3422/3/4 devices can be used for various
precision
These devices operate with very simple connections to
the application circuit. The following sections discuss
the examples of the device connections and
applications.
6.1
6.1.1
For an accurate measurement, the application circuit
needs a clean supply voltage and must block any noise
signal to the MCP3422/3/4 devices.
an example of using two bypass capacitors (a 10 µF
tantalum capacitor and a 0.1 µF ceramic capacitor) on
the V
helpful to filter out any high frequency noises on the
V
extra currents when the device needs from the supply.
These capacitors should be placed as close to the V
pin as possible (within one inch). If the application
circuit has separate digital and analog power supplies,
the V
reside on the analog plane.
6.1.2
The SCL and SDA pins of the MCP3422/3/4 are open-
drain configurations. These pins require a pull-up
resistor as shown in
pull-up resistors depends on the operating speed
(standard, fast, and high speed) and loading
capacitance of the I
resistor consumes less power, but increases the signal
transition time (higher RC time constant) on the bus.
Therefore, it can limit the bus operating speed. The
lower value of resistor, on the other hand, consumes
higher power, but allows higher operating speed. If the
bus line has higher capacitance due to long bus line or
high number of devices connected to the bus, a smaller
pull-up resistor is needed to compensate the long RC
time constant. The pull-up resistor is typically chosen
between 5 kΩ and 10 kΩ ranges for standard and fast
modes, and less than 1 kΩ for high speed mode
depending on the presence of bus loading capacitance.
© 2009 Microchip Technology Inc.
DD
line and also provide the momentary bursts of
DD
DD
and V
BASIC APPLICATION
CONFIGURATION
Connecting to the Application
Circuits
line of the MCP3424. These capacitors are
analog-to-digital
BYPASS CAPACITORS ON V
CONNECTING TO I
PULL-UP RESISTORS
SS
of the MCP3422/3/4 devices should
2
C bus line. Higher value of pull-up
Figure
6-1. The value of these
converter
2
C BUS USING
Figure 6-1
applications.
DD
shows
PIN
DD
6.1.3
The user can tie the Adr0 and Adr1 pins to V
or left floating. See more details in Section 5.3.2
“Device Address Bits (A2, A1, A0) and Address
Selection Pins (MCP3423 and MCP3424)”.
FIGURE 6-1:
Figure 6-2
connections. The I
increases as the number of device connected to the I
bus line increases. The bus loading capacitance affects
on the bus operating speed. For example, the highest
bus operating speed for the 400 pF bus capacitance is
1.7 MHz, and 3.4 MHz for 100 pF. Therefore, the user
needs to consider the relationship between the
maximum operation speed versus. the number of I
devices that are connected to the I
FIGURE 6-2:
Connection on I
Input
Signal 2
Signal 1
Input
Rp is the pull-up resistor:
C1: 0.1 µF, Ceramic capacitor
C2: 10 µF, Tantalum capacitor
5 kΩ - 10 kΩ for f
Microcontroller
(PIC16F876)
C
~700Ω for f
C
1
2
I
(
shows an example of multiple device
2
MCP3423
MCP3424
C ADDRESS SELECTION PINS
2
4
5
6
7
1
3
R
2
P
C Bus.
SCL
SCL
CH1+
CH1-
CH2+
V
V
SDA
CH2-
MCP3422/3/4
SS
DD
MCP3424
2
Typical Connection.
Example of Multiple Device
C bus loading capacitance
AND
=
=
SDA SCL
100 kHz to 400 kHz
3.45 MHz
CH3+
CH4+
MCP3424
CH4-
CH3-
Adr1
Adr0
SCL
14
13
12
11
10
2
9
8
R
C bus line.
MCP3422
MCP3423
P
DS22088C-page 31
MCP4725
)
(MASTER)
I
Selection
Pins
T
2
Signal 4
Input
O
Signal 3
C Address
Input
SS
MCU
V
DD
, V
DD
2
2
C
C
,