PTC Heater Self-Regulation for Optical Transceiver Temperature Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing optical transceivers face challenges in controlling temperature without additional control circuits, leading to increased power consumption and limited temperature range, especially in low-density coarse wavelength division multiplexing (CWDM) optical modules, which affects performance and costs.

Innovation Solution

The use of a positive temperature coefficient (PTC) heater made of BaTiO3 material, coupled with a laser diode and a stem body, which self-heats and is controlled by a thermistor and switching unit to adjust heating based on ambient temperature, reducing power consumption and expanding the temperature range without separate control apparatuses.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a general heater is used to control temperature, then temperature stability is improved, but device complexity increases due to additional control circuits and PCB layers

Engineering Contradiction:

Improvetemperature stabilityVSAvoidcontrol circuit complexity

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The PTC heater element automatically regulates its own temperature through its intrinsic positive temperature coefficient特性. When the temperature rises, the resistance increases, automatically reducing the current and heating power without requiring external control circuits, sensors, or feedback mechanisms. This self-regulating property eliminates the need for separate temperature control circuitry while maintaining temperature stability.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The invention extracts and utilizes the inherent temperature-regulating property of the PTC material itself, separating the heating function from the control function. The PTC heater element contains the control logic within its material properties rather than requiring external electronic control systems, thereby simplifying the overall device architecture.

Inventive Principle:

Principle #2Taking out (Extraction)

2Temperature

If a cooled laser diode using TEC is used, then wavelength stability is improved, but manufacturing cost increases due to TEC materials and assembly difficulty

Engineering Contradiction:

Improvewavelength stabilityVSAvoidmanufacturing cost

Core Design Contradiction:

TemperatureVSEase of manufacture

Solution Approach 1:

The PTC heater element is a simple, inexpensive ceramic component that can be easily manufactured and replaced if needed. Unlike TEC modules which require precision manufacturing and complex assembly, the PTC heater is a robust, low-cost component that achieves temperature control without the high manufacturing costs associated with thermoelectric coolers.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The invention replaces the mechanical and electronic complexity of TEC systems with a simple resistive heating element whose temperature control emerges from its electrical properties. This substitution eliminates the need for complex thermoelectric modules, control circuits, and precision assembly procedures.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Adaptability or versatility

If temperature control circuits are added to expand temperature range, then adaptability is improved, but power consumption increases

Engineering Contradiction:

Improvetemperature rangeVSAvoidpower consumption

Core Design Contradiction:

Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The PTC heater operates in a natural oscillating manner: as temperature rises, resistance increases, reducing current and heating power; as temperature falls, resistance decreases, increasing current and heating power. This automatic periodic adjustment maintains the desired temperature range while consuming only the minimum necessary power, without requiring continuous high-power control circuit operation.

Inventive Principle:

Principle #19Periodic action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution significantly reduces power consumption and expands the temperature range of optical transceivers from -40°C to 85°C, simplifying assembly and minimizing product volume by eliminating the need for separate control circuits and improving wavelength stability.

Implementation Method 1

a positive temperature coefficient (PTC) heater which is coupled with the stem body to be self-heated

Methodology Applied

Scientific EffectJoule heating: Joule Heating

Data Source

PatentUS9335770B2Optical transceiver capable of controlling self-heating according to temperature

Publication Date: 2016.05.10 LIGHTRON FIBER OPTIC DEVICES

AI summary

Disclosed is an optical transceiver capable of controlling self-heating according to temperature, more particularly, an optical transceiver which uses a PTC heater suitable for temperature characteristics to easily control self-heating. A PTC heater of which the self-resistance changes depending on the ambient temperature of uncooled laser diodes of an optical transceiver so as to adjust heating volume of the heater, is applied to a TO CAN, thus making it possible to significantly reduce power consumption while expanding an available temperature range of existing optical modules, even without a separate controller or using a minimum number of control circuits.