JP2007019119A - Optical transmitting and receiving module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical transmitting and receiving module which is made compact and can perform the temperature compensated control of the transmitting and receiving sides by the small number of components, and which especially can perform a temperature compensated control of the transmitting side in parallel with the control of the receiving side by using the temperature information obtained from a temperature-sensitive element used for controlling the receiving side. <P>SOLUTION: The optical transmitting and receiving module includes an optical characteristic stabilizing control circuit which simultaneously controls the forward current value of a laser diode incorporating a laser module, the driving offset voltage, voltage amplitude, and duty cycle of a driver IC in parallel, by the information from the temperature-sensitive element mounted on the receiving side via an arithmetic portion or a buffer amplifier. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical transceiver module that performs temperature compensation of a transmission unit using a temperature compensation thermistor provided in a reception unit.

  As communication demand increases, data communication needs to be made faster and more multifunctional. As a result, optical transceiver modules are desired to be smaller and consume less power. However, due to the deterioration of heat dissipation due to miniaturization, the effect of changes in ambient temperature on internal components with temperature characteristics is a bigger problem than before. It has become.

  In order to compensate for this, there is a method described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2002-111120) as a technique for arranging a thermistor serving as a temperature sensor in the vicinity of the component and performing compensation according to a temperature change. . However, this is only applicable to direct modulation laser modules. In addition, in order to perform temperature compensation of components mounted on an optical transceiver module with a minimum number of components and circuit configuration, it is necessary to perform temperature compensation by simultaneously controlling multiple parameters with a single temperature sensor. There is.

JP 2002-111120 A

  An object of the present invention is to provide an optical transmission / reception module capable of performing temperature compensation of a component that has a large characteristic variation due to an ambient temperature and has a large influence on optical transmission characteristics, with a limited number of components of an optical module to be miniaturized. .

  In order to solve the above problems, in the present invention according to claim 1, a laser module or an external modulator integrated laser module, a driver IC that drives the laser module, and a PIN-PD or APD that uses a temperature sensitive element are provided. In an optical transceiver equipped with the receiving module used, the temperature compensation control of the laser module and the driver IC for driving the laser module is simultaneously performed in parallel using the temperature sensitive element information used for the receiving side control. Features.

  According to a second aspect of the present invention, in the optical characteristic stabilization control circuit according to the first aspect, the information obtained from the temperature sensing element is constituted by an arithmetic unit such as a microcomputer, FPGA or CPLD via a digital conversion circuit. It is possible to input to the calculation unit, reconvert the calculation result into an analog value, and control the forward current value of the laser diode built in the laser module, the drive offset voltage, voltage amplitude, and duty cycle of the driver IC simultaneously in parallel. It is characterized by things.

  According to a third aspect of the present invention, in the optical characteristic stabilization control circuit according to the first aspect, the temperature information obtained from the temperature-sensitive element remains in an analog value via a buffer amplifier, and the order of the laser diodes built in the laser module. The current value, the drive offset voltage of the driver IC, the voltage amplitude, and the duty cycle can be simultaneously controlled in parallel.

  A fourth aspect of the present invention is characterized in that the temperature sensitive element according to the first aspect is incorporated in a receiving module.

  The invention according to claim 5 is characterized in that the temperature sensitive element according to claim 1 is mounted in an optical transceiver module substrate.

  According to a sixth aspect of the present invention, in the temperature compensation control according to the first aspect, the forward current value of the laser diode to be temperature compensated control and each parameter of the drive driver IC are individually optimized based on the characteristics of the external modulator. Is calculated in advance, stored in a built-in or external memory as a temperature compensation coefficient, and controlled based on the stored temperature compensation coefficient.

  According to a seventh aspect of the present invention, in the temperature compensation control according to the first aspect, the forward current value of the laser diode to be subjected to the temperature compensation control and each parameter of the drive driver IC are individually optimized based on the characteristics of the external modulator. Is calculated in advance, stored in a built-in or external memory as a look-up table, and controlled based on the stored look-up table.

  The invention according to claim 8 is the transmitter / receiver according to claim 1, wherein the driver is incorporated in the external modulator integrated laser module, receives the same temperature control means, and the target value of the control temperature is It is controlled based on the temperature information of claim 6.

  According to the present invention, a temperature-sensitive element mounted on the receiving side is used to suppress the temperature fluctuation of a component that greatly affects the transmission characteristics on the transmitting side, and to an optical transceiver module that is downsized and highly integrated. Can respond.

  Details of the present invention will be described below with reference to the drawings.

  FIG. 2 shows a first embodiment of the present invention. The information of the PD module built-in thermistor 110 mounted on the PD module 108 is converted into a digital value by the (digital conversion circuit), and the resistance value of the (digital variable resistance) is changed by the result of the calculation by (FPGA). The control voltage of (driver IC) is changed.

  In this embodiment, the arithmetic unit is configured by (digital conversion circuit), (FPGA), and (digital variable resistor), but a microcomputer in which two or all of these are integrated may be used. Further, (FPGA) may be another electronic component capable of digital calculation. The (digital variable resistor) may be another electronic component such as a D / A converter that can convert the digital output of the arithmetic device into an analog signal.

  FIG. 3 shows a second embodiment of the present invention. (Temperature sensing element) information mounted on (receiving module) is level-converted by (buffer amplifier, level converter) and superimposed on the voltage output from (control voltage adjustment circuit) of (driver IC) Change the control voltage.

It is a figure which shows the functional block of an optical transmitter / receiver. 1 is a first embodiment of the present invention. It is a 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Electric signal input terminal, 102 ... Driver IC, 103 ... Automatic output control apparatus, 104 ... Laser module, 105 ... Optical output signal, 106 ... Automatic temperature control apparatus, 107 ... PD module control device, 108 ... PD module, 109 ... electric signal output terminal, 110 ... PD module built-in thermistor, 111 ... optical signal input, 112a ... driver IC drive offset voltage Control terminal, 112b... Driver IC voltage amplitude control terminal, 112c... Driver IC duty cycle control terminal, 113a... Driver IC drive offset voltage control variable adjustment resistor,
113b: Variable resistance for adjusting the driver IC voltage amplitude control voltage, 113c: Variable resistor for adjusting the driver IC duty cycle control voltage, 201 ... Electric signal input terminal, 202 ... Driver IC, 203 ... Automatic output controller 204 ... Laser module 205 ... Light output signal 206 ... Automatic temperature controller 207 ... PD module controller 208 ... PD module 209 Electric Signal output terminal 210 ... PD module built-in thermistor 211 ... Optical signal input 212a ... Driver IC drive offset voltage control terminal 212b ... Driver IC voltage amplitude control terminal 212c ... Driver IC Duty cycle control terminal, 213... Digital / analog conversion circuit, 214. 215: Analog / digital conversion circuit, 301: Electric signal input terminal, 302: Driver IC, 303 ... Automatic output control device, 304 ... Laser module, 305 ... Optical output signal, 306 ... Automatic temperature control device, 307 ... PD module control device, 308 ... PD module, 309 ... Electric signal output terminal, 310 ... PD module built-in thermistor, 311 ... Optical signal input , 312a ... Driver IC drive offset voltage control terminal, 312b ... Driver IC voltage amplitude control terminal, 312c ... Driver IC duty cycle control terminal, 313a ... Variable resistor for adjusting driver IC drive offset voltage control voltage 313b... Driver IC voltage amplitude control voltage adjustment variable resistor, 313c. Driver IC duty cycle control voltage adjusting variable resistor,
314a: buffer amplifier a, 314b: buffer amplifier b, 314c: buffer amplifier c, 314d: buffer amplifier d, 314e: buffer amplifier e

Claims (8)

In an optical transceiver equipped with a laser module or an external modulator integrated laser module, a driver IC for driving the laser module, and a receiver module using a PIN-PD or APD using a temperature sensitive element,
An optical characteristic stabilization control circuit, wherein temperature compensation control of the laser module and the driver IC for driving the laser module is simultaneously performed in parallel using temperature sensing element information used for the receiving side control.   The optical characteristic stabilization control circuit according to claim 1, wherein information obtained from the temperature sensing element is input to a calculation unit including a calculation device such as a microcomputer, FPGA, or CPLD via a digital conversion circuit. The result of the calculation is converted back to an analog value, and one or more or all of the forward current value, element temperature, driver offset voltage, voltage amplitude, and duty cycle of the laser diode built in the laser module are simultaneously processed in parallel. 2. The optical characteristic stabilization control circuit according to claim 1, wherein the optical characteristic stabilization control circuit can be controlled.   2. The optical characteristic stabilization control circuit according to claim 1, wherein the information obtained from the temperature-sensitive element remains in an analog value via a buffer amplifier, and the forward current value of the laser diode built in the laser module, the element temperature 2. The optical characteristic stabilization control circuit according to claim 1, wherein one or more or all of the drive offset voltage, voltage amplitude, and duty cycle of the driver IC can be simultaneously controlled in parallel.   An optical characteristic stabilization control circuit comprising the temperature sensing element according to claim 1 incorporated in a receiving module.   An optical characteristic stabilization control circuit, wherein the temperature sensitive element according to claim 1 is mounted in an optical transceiver module substrate. An optical property stabilization control circuit according to claim 1,
In the temperature compensation control, the forward current value of the laser diode to be temperature compensated control, the element temperature, and each parameter of the drive driver IC are individually calculated in advance based on the characteristics of the external modulator, An optical characteristic stabilization control circuit characterized in that a temperature compensation coefficient is stored in a memory and controlled based on the stored temperature compensation coefficient. An optical property stabilization control circuit according to claim 1,
In the temperature compensation control, the forward current value of the laser diode to be temperature compensated control, the element temperature, and each parameter of the drive driver IC are individually calculated in advance based on the characteristics of the external modulator, An optical characteristic stabilization control circuit, wherein a lookup table is stored in a memory and controlled based on the stored lookup table. An optical property stabilization control circuit according to claim 1,
In the transceiver, the driver is incorporated in the external modulator integrated laser module, receives the same temperature control means, and the target value of the control temperature is controlled based on the temperature information of claim 6. An optical characteristic stabilization control circuit characterized by comprising:

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