Microchip MCP6272 Manual

Microchip Ikke kategoriseret MCP6272

Læs gratis den danske manual til Microchip MCP6272 (14 sider) i kategorien Ikke kategoriseret. Denne vejledning er vurderet som hjælpsom af 15 personer og har en gennemsnitlig bedømmelse på 4.3 stjerner ud af 8 anmeldelser. Har du et spørgsmål om Microchip MCP6272, eller vil du spørge andre brugere om produktet?

Download PDF
Side 1/14
© 2006 Microchip Technology Inc. DS00897C-page 1
AN897
INTRODUCTION
This application note shows two designs that use a
precise, negative temperature coefficient (NTC)
thermistor for temperature measurement. The
thermistor is placed in a resistive divider to linearize the
temperature-to-voltage conversion. The voltage is
processed in the analog domain by the MCP6SX2
(MCP6S22 or MCP6S92) Programmable Gain
Amplifier (PGA) before conversion to the digital
domain.
The first design is simpler and has a smaller
temperature range. The second design changes the
PGA’s gain to achieve a greater temperature range.
Both designs use a piece-wise linear interpolation table
to correct the remaining non-linearity and convert
voltage into degrees Celsius. The design trade-offs
between these approaches will be discussed.
These circuits take advantage of the MCP6SX2’s input
multiplexer (MUX). The PGA is used to process
multiple signals and/or temperatures and digitally sets
the most appropriate gain for each input. This reduces
overall design complexity and allows for temperature
correction of other sensors.
THERMISTOR
The thermistor used in the application note is part
number 2322 640 55103 from BC Components
®; see
Figure 1 and Figure 2. This part is selected for its
accuracy and cost. The thermistor’s temperature is
TTH, while the rest of the circuit is at ambient
temperature TA.
FIGURE 1: Thermistor Response.
Key specifications include [1, 2]:
• Resistance at +25°C: 10 kΩ ± 1%
• B25/85 tolerance: ±0.75%
• Operating temperature range: -40°C to +125°C
(to +150°C for short periods)
• Maximum power
- 100 mW, TTH = 0°C to +55°C
- 100% de-rated at TTH = -40°C and +85°C
• Thermal dissipation factor: 2.2 mW/°C
• Response time: 1.7 s (in oil)
FIGURE 2: Thermistor Accuracy.
Thermistors with different price and accuracy trade-offs
may also be used in this application. It is simple to
modify the circuits to match the desired accuracy.
CIRCUIT
The circuit shown in Figure 3 is used for both designs
described later. It is implemented on the MCP6SX2
PGA Thermistor PICtail™ Demo Board; see reference
[12].
The resistor RA makes the voltage vs. temperature
response reasonably linear. RB and CB reduce the
noise and act as an anti-aliasing filter for the ADC. The
MCP6SX2 PGA (MCP6S22 [5] or MCP6S92 [6])
buffers the voltage VDIV
. The PGA can be digitally
controlled to change its gain or channel (input).
The PIC16F684 [8] is on the Signal Analysis PICtail™
Daughter Board; see reference [11]. It has an internal
10-bit ADC that converts VOUT to the digital domain. It
can further process VOUT (e.g., averaging) and convert
it to temperature. It communicates with the PGA via the
SPI serial bus.
Author: Kumen Blake and Steven Bible
Microchip Technology Inc.
100
1000
10000
100000
1000000
-50 -25 0 25 50 75 100 125 150
Thermistor Temperature (°C)
Thermistor Resistance (
:
:
:
::
)
100
1k
10k
100k
1M
BC Components®
# 2322 640 55103
10 k
:
:
:
::
@ +25°C
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
-50 -25 0 25 50 75 100 125 150
Thermistor Temperature (°C)
Thermistor Error Magnitude
(°C)
BC Components
®
# 2322 640 55103
10 kΩ
Ω
Ω
ΩΩ @ +25°C
Thermistor Temperature Sensing with MCP6SX2 PGAs

Produkt Specifikationer

Mærke: Microchip
Kategori: Ikke kategoriseret
Model: MCP6272

Har du brug for hjælp?

Hvis du har brug for hjælp til Microchip MCP6272 stil et spørgsmål nedenfor, og andre brugere vil svare dig


Ikke kategoriseret Microchip Manualer

Microchip

Microchip PIC16F87 Manual

25 Oktober 2025
Microchip

Microchip PIC18F2620 Manual

25 Oktober 2025
Microchip

Microchip RN240 Manual

24 Oktober 2025
Microchip

Microchip PIC24HJ12GP201 Manual

24 Oktober 2025
Microchip

Microchip TC4420 Manual

24 Oktober 2025
Microchip

Microchip HV2818 Manual

23 Oktober 2025
Microchip

Microchip MIC2298 Manual

23 Oktober 2025
Microchip

Microchip PIC16F630 Manual

23 Oktober 2025
Microchip

Microchip PIC32MZ2048EFG144 Manual

21 Oktober 2025
Microchip

Microchip PIC18F46J50 Manual

21 Oktober 2025

Ikke kategoriseret Manualer

Nyeste Ikke kategoriseret Manualer

Scott

Scott Essential 09989 Manual

5 November 2025
BlueShape

BlueShape Granite Link AP Manual

5 November 2025
EtherWAN

EtherWAN OttoE 10H Manual

5 November 2025
Infiniton

Infiniton Belcanto49C1 Manual

5 November 2025
Intermatic

Intermatic WP1250MXD Manual

5 November 2025
INIU

INIU P63-P1 Manual

5 November 2025
D'Addario

D'Addario PW-XPND-01 Manual

5 November 2025
DS18

DS18 VOC8PRO Manual

5 November 2025
Icron

Icron Rover 2850 Manual

5 November 2025
Amaran

Amaran Peak Manual

5 November 2025