INA330 Datasheet, PDF (1/14 Pages) Burr-Brown (TI) – THERMISTOR SIGNAL AMPLIFIER FOR TEMPERATURE CONTROL

INA330
INA330
SBOS260 – NOVEMBER 2002
THERMISTOR SIGNAL AMPLIFIER
FOR TEMPERATURE CONTROL
FEATURES
q OPTIMIZED FOR PRECISION 10kΩ
THERMISTOR APPLICATIONS
q LOW OFFSET OVER TEMPERATURE:
0.009°C Temperature Error, –40°C to +85°C
q EXCELLENT LONG-TERM STABILITY
q VERY LOW 1/f NOISE: (0.01Hz to 10Hz)
(Peak-to-Peak Equivalent to 0.0001°C)
q WIDE OUTPUT SWING: Within 10mV of Rails
q SUPPLY RANGE: Single +2.7V to +5.5V
q microPACKAGE: MSOP-10
q REQUIRES ONLY ONE PRECISION RESISTOR
APPLICATIONS
q THERMISTOR-BASED TEMPERATURE
CONTROLLERS FOR OPTICAL NETWORKING
q HIGH ACCURACY FOR TEC APPLICATIONS
q LASER TEMPERATURE CONTROL
DESCRIPTION
The INA330 is a precision amplifier designed for thermoelec-
tric cooler (TEC) control in optical networking applications. It
is optimized for use in 10kΩ thermistor-based temperature
controllers. The INA330 provides thermistor excitation and
generates an output voltage proportional to the difference in
resistances applied to the inputs. It uses only one precision
resistor plus the thermistor, thus providing an alternative to
the traditional bridge circuit. This new topology eliminates the
need for two precision resistors while maintaining excellent
accuracy for temperature control applications.
An excitation voltage is applied to the thermistor (R_THERM)
and precision resistor (R_SET), creating currents I₁ and I₂. The
current conveyor circuit produces an output current, I_O, equal
to I₁ – I₂, which flows through the external gain-setting
resistor. A buffered voltage output proportional to I_O is also
provided.
The INA330 offers excellent long-term stability, and very low
1/f noise throughout the life of the product. The low offset
results in a 0.009°C temperature error from –40°C to +85°C.
It comes in MSOP-10 packaging and operates with supply
voltages from +2.7V to +5.5V. It is specified over the indus-
trial temperature range, –40°C to +85°C, with operation from
–40°C to +125°C.
V_EXCITE
1V
V₂
2
V₁
3
V+
95
Enable High = On
Low = Off
6
8
V_O
PID CONTROLLER
V_REF
2.5V
I₁
Thermistor
R_THERM = 10kΩ
10
1
I₂
R_SET
10kΩ
7
I_O = I₁ – I₂
4
C_FILTER
500pF
R_G
200kΩ
V_ADJUST = +2.5V
D/A
Converter
INA330 In A Temperature Control Loop
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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Copyright © 2002, Texas Instruments Incorporated