Features and Benefits
- High Efficiency, Low Noise Topology
- Adjustable Output Slew Rate Reduces EMI
- Full-Bridge Controller for Bidirectional Current Control
- Adjustable Pulse-by-Pulse Bidirectional TEC Current Limit
- Open/Shorted Thermistor Indication
- Solution Footprint in Less Than 0.6" x 0.8"
- Available in 5mm x 5mm QFN and 28-Pin SSOP Packages
- TEC Voltage Clamping
- TEC Current, Voltage and Heat/Cool Status Outputs
- Adjustable/Synchronizable Oscillator Frequency Reduces Filter Component Size and System Noise
- 2.5V Reference Voltage Output
- 2.7V Minimum Operating Voltage
The LTC1923 is a pulse width modulator intended for thermoelectric cooler (TEC) or heater applications requiring either unidirectional or bidirectional drive circuits. All of the necessary control circuitry and two sets of complementary output drivers are integrated into the LTC1923 to drive a full bridge, providing an efficient means of bidirectional current flow to the TEC. An accurate temperature control loop to stabilize the temperature of a laser diode system is easily achieved with the addition of just a few external components. Typical temperature setpoint accuracy of 0.1°C is achievable with the LTC1923. Adding an instrumentation amplifier front end allows setpoint stability of 0.01°C.
The part features independent adjustable heating and cooling pulse-by-pulse current limit, current soft-start for controlled start-up, output slew rate control to reduce system noise, differential current sense and voltage amplifiers and a host of auxiliary circuits to protect the laser and provide redundant system monitoring.
- Laser-Based Fiber Optic Links
- Medical Instruments
- CPU Temperature Regulators
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (2)
Demonstration circuit DC388 utilizes the LTC1923 thermoelectric cooler (TEC) controller. It provides a complete temperature control solution for TEC based temperature control of fiber-optic lasers. Laser temperature may be controlled at temperatures above or below ambient with set point stability typically well within .05º C over widely varying ambient temperature. Temperature set point is established with a screwdriver driven potentiometer or a 14-bit on-board DAC. Considerably more detail relating to TEC temperature control issues is available in LTC Application Note AN-89, “A Thermoelectric Cooler Temperature Controller for Fiber Optic Lasers.” This publication should be reviewed before demo board results are evaluated.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.