FEATURES

OPTIMIZED FOR PRECISION 10kΩ

THERMISTOR APPLICATIONS

LOW OFFSET OVER TEMPERATURE:

0.009°C Temperature Error, –40°C to +85°C

EXCELLENT LONG-TERM STABILITY

VERY LOW 1/f NOISE: (0.01Hz to 10Hz)

(Peak-to-Peak Equivalent to 0.0001°C)

WIDE OUTPUT SWING: Within 10mV of Rails

SUPPLY RANGE: Single +2.7V to +5.5V

microPACKAGE: MSOP-10

REQUIRES ONLY ONE PRECISION RESISTOR

APPLICATIONS

THERMISTOR-BASED TEMPERATURE

CONTROLLERS FOR OPTICAL NETWORKING

HIGH ACCURACY FOR TEC APPLICATIONS

LASER TEMPERATURE CONTROL

DESCRIPTION

The INA330 is a precision amplifier designed for thermoelectric

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 (RTHERM)

and precision resistor (RSET), creating currents I1 and I2. The

current conveyor circuit produces an output current, IO, equal

to I1 – I2, which flows through the external gain-setting

resistor. A buffered voltage output proportional to IO 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 industrial

temperature range, –40°C to +85°C, with operation from

–40°C to +125°C.