Low-noise power supply circuit for optical module

Abstract

The utility model provides a low-noise power supply circuit for an optical module in the technical field of optical modules. The low-noise power supply circuit comprises a primary voltage regulating module, a secondary voltage regulating module, a voltage feedback module and an upper computer, the first-stage voltage regulating module, the second-stage voltage regulating module, the voltage feedback module and the first-stage voltage regulating module are connected in sequence; the upper computer is connected with the primary voltage regulating module; the secondary voltage regulation module comprises a voltage regulation chip U2, a resistor R6, a resistor R7, a capacitor C2, a capacitor C3, a capacitor C4 and a capacitor C5; after the C2 and the C3 are connected in parallel, one end is grounded, and the other end is connected with pins 6, 7 and 8 of the U2, the primary voltage regulating module and the voltage feedback module; one end of the C4 is connected with the pin 5 of the U2, and the other end is grounded; a pin 1 and a pin 2 of the U2 are connected with one end of the R6, one end of the C5 and the voltage feedback module, and a pin 3 is connected with the other end of the R6, the other end of the C5 and one end of the R7; and the R7 is connected with a pin 4 of the U2. The low-noise power supply circuit has the advantages that the power consumption and the cost of the low-noise power supply circuit are greatly reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to optical module technical field, especially point to a kind of low-noise power supply circuit for optical module. BACKGROUND

[0002] Optical module is photoelectric conversion and electro-optical conversion optoelectronic device, according to the protocol and specification of optical module, the total power input of optical module is generally 3.3V voltage, and 3.3V voltage needs to be converted into multiple different power supply voltages of different level in optical module to power supply different subsystems in optical module, such as 0.65V, 0.94V, 1.2V, 1.8V, 2.5V, 3.3V, 4V, 5V voltage.

[0003] To realize the voltage conversion of different levels, multiple different power conversion chips will be used in optical module, and a part of subsystems have high requirements for voltage stability and power supply noise (power supply ripple), such as DSP power supply circuit, clock source, reference level loop, etc., especially with the rate of optical module improving to 400G&800G&1.6T, the requirement for power supply noise is more strict, and multiple subsystems require power supply ripple to be controlled below 1mV, and conventional boost (BOOST) power chip or buck (DC-DC) power chip cannot meet the power supply ripple requirement, so a low-noise power chip such as LDO needs to be used after power conversion chip to adjust voltage and control ripple, so as to ensure that power supply ripple meets the design requirement.

[0004] The low-noise power supply circuit for optical module is generally divided into the following two power supply circuits: circuit one is a power supply circuit with low-noise requirement and greater than 3.3V, and circuit two is a power supply circuit with low-noise requirement and less than 3.3V. Circuit one is composed of a first boost module (refer to Figure 3 ) and a first buck module (refer to Figure 4 ); circuit two is composed of a second buck module (refer to Figure 5 ) and a third buck module (refer to Figure 6 ).

[0005] The working principle of circuit one from 3.3V to 4V is as follows: by adjusting the resistance value of resistor R12 and resistor R13, 3.3V power supply is boosted to 5V in combination with power chip U11 (BOOST chip); by adjusting the resistance value of resistor R15 and resistor R16, 5V power supply is reduced to 4V in combination with power chip U12 (LDO chip). VCC5V_EN and VCC4V_EN are used as upper computer control signals to control the enablement of power chip U11 and power chip U12 to work.

[0006] The working principle of the loop two from 3.3V to 1.2V is as follows: 3.3V power supply is reduced to 1.8V by adjusting the resistance values of resistors R18 and R19 and combining the power chip U21 (DC-DC chip); 1.8V power supply is reduced to 1.2V by adjusting the resistance values of resistors R21 and R2 and combining the power chip U22 (LDO chip). VCC1V8_EN and VCC1V2_EN are used as upper computer control signals for controlling the power chips U21 and U22 to work.

[0007] The traditional low-noise power supply circuit has the following disadvantages: 1. Different power chips are needed to perform step-up or step-down processing for step-up and step-down requirements, the step-up and step-down circuits are not compatible, the number of chip materials is increased, and thus the circuit cost is increased; 2. The power chips of the primary power supply (the first step-up module and the second step-down module) and the secondary power supply (the first step-down module and the third step-down module) need to be controlled respectively, in order to maintain the stable operation of the circuit, the output voltage of the first stage power supply needs to have sufficient margin, which will cause the voltage difference of the LDO chip of the secondary power supply to increase; since the working principle of the LDO chip is to keep the input and output currents the same, the LDO chip is controlled to work through the internal MOS tube, so as to achieve the goal of stable voltage drop and low noise, therefore, the energy loss caused by the voltage difference between the output end and the input end of the LDO chip in the loop will be all the heat dissipation of the LDO chip, which will cause the LDO chip to generate more heat; 3. The power chips of the primary power supply and the secondary power supply need to be controlled independently, and the EN signals output by the upper computer are needed for controlling the power chips to work, that is, a large number of IO resources are occupied, and the circuit cost is increased.

[0008] Therefore, how to provide a low-noise power supply circuit for an optical module to reduce the power consumption and cost of the low-noise power supply circuit has become a technical problem to be solved. SUMMARY

[0009] The technical problem to be solved by the utility model is to provide a low-noise power supply circuit for an optical module to reduce the power consumption and cost of the low-noise power supply circuit.

[0010] The utility model is implemented in the following way: a low-noise power supply circuit for an optical module, comprising a primary voltage regulating module, a secondary voltage regulating module, a voltage feedback module and an upper computer; the primary voltage regulating module, the secondary voltage regulating module, the voltage feedback module and the primary voltage regulating module are connected in sequence; the upper computer is connected with the primary voltage regulating module;

[0011] The secondary voltage regulating module comprises a voltage regulating chip U2, a resistor R6, a resistor R7, a capacitor C2, a capacitor C3, a capacitor C4 and a capacitor C5;

[0012] The capacitor C2 is connected with the capacitor C3 in parallel, one end is grounded, and the other end is connected with the pin 6, 7 and 8 of the voltage regulating chip U2, the first-stage voltage regulating module and the voltage feedback module; one end of the capacitor C4 is connected with the pin 5 of the voltage regulating chip U2, and the other end is grounded;

[0013] The pin 1 and 2 of the voltage regulating chip U2 are connected with one end of the resistor R6, one end of the capacitor C5 and the voltage feedback module, the pin 3 is connected with the other end of the resistor R6, the other end of the capacitor C5 and one end of the resistor R7; the other end of the resistor R7 is connected with the pin 4 of the voltage regulating chip U2 and grounded.

[0014] Further, the first-stage voltage regulating module comprises a voltage regulating chip U1, an inductor L1, a resistor R1 and a capacitor C1.

[0015] The pin 1 of the voltage regulating chip U1 is connected with the capacitor C1, the pin 2 is connected with the resistor R1 and the upper computer, the pin 4 is connected with one end of the inductor L1, the pin 5 is connected with the other end of the inductor L1, the pins 6 and 9 are grounded, the pin 7 is connected with one end of the capacitor C2, one end of the capacitor C3, the pins 6, 7 and 8 of the voltage regulating chip U2 and the voltage feedback module, and the pin 8 is connected with the voltage feedback module.

[0016] Further, the voltage feedback module comprises a resistor R2, a resistor R3, a resistor R4 and a resistor R5.

[0017] One end of the resistor R2 is connected with the first-stage voltage regulating module, and the other end is connected with one end of the resistor R3, one end of the resistor R4 and one end of the resistor R5; the other end of the resistor R3 is connected with the first-stage voltage regulating module; the other end of the resistor R4 is grounded; and the other end of the resistor R5 is connected with the pins 1 and 2 of the voltage regulating chip U2.

[0018] The utility model has the advantages of:

[0019] By setting a first voltage regulating module, a second voltage regulating module and a voltage feedback module, and the first voltage regulating module, the second voltage regulating module, the voltage feedback module and the first voltage regulating module are connected in sequence; the voltage regulating chip U1 of the first voltage regulating module has the functions of voltage boosting and voltage reducing, and can meet the requirements of voltage boosting and voltage reducing on the basis of the voltage drop of the voltage regulating chip U2 of the second voltage regulating module, without using different power supply chips for processing, reducing the types of chip materials, and reducing the number of IO resources occupied by the upper computer; the second output voltage of the second voltage regulating module is collected by the voltage feedback module and fed back to the first voltage regulating module, so that the first voltage regulating module can dynamically adjust the first output voltage, without maintaining a sufficient margin for the first output voltage as in the traditional way, effectively reducing the voltage difference of the voltage regulating chip U2 of the second voltage regulating module, reducing the heat dissipation of the voltage regulating chip U2, greatly reducing the power consumption and cost of the low-noise power supply circuit, and also improving the overcurrent capacity of the voltage regulating chip U2, reducing the power consumption and cost of the entire low-noise power supply circuit. BRIEF DESCRIPTION OF DRAWINGS

[0020] The utility model will be further described below with reference to the drawings in combination with the embodiments.

[0021] Figure 1 It is a circuit principle block diagram of a low-noise power supply circuit for an optical module of the utility model.

[0022] Figure 2 It is a circuit diagram of a low-noise power supply circuit for an optical module of the utility model.

[0023] Figure 3 It is a circuit diagram of the first voltage boosting module of the traditional circuit one.

[0024] Figure 4 It is a circuit diagram of the first voltage reducing module of the traditional circuit one.

[0025] Figure 5 It is a circuit diagram of the second voltage reducing module of the traditional circuit two.

[0026] Figure 6 It is a circuit diagram of the third voltage reducing module of the traditional circuit two. DETAILED DESCRIPTION

[0027] The technical scheme in the embodiments of the present application has the following general idea: the voltage regulating chip U1 of the first voltage regulating module has the functions of voltage increase and voltage decrease, can meet the requirements of voltage increase and voltage decrease on the basis of the voltage drop of the voltage regulating chip U2 of the second voltage regulating module, reduces the types of materials of chips, and also reduces the number of occupied IO resources of the upper computer; the second output voltage of the second voltage regulating module is collected by the voltage feedback module and fed back to the first voltage regulating module, so that the first voltage regulating module can dynamically adjust the first output voltage, without keeping the first output voltage with a sufficient margin as in the prior art, effectively reducing the voltage difference of the voltage regulating chip U2 of the second voltage regulating module, thereby reducing the heat dissipation of the voltage regulating chip U2 and the power consumption and cost of the low-noise power supply circuit.

[0028] Please refer to Figures 1 to 6 The preferred embodiment of the low-noise power supply circuit for an optical module of the utility model, including a first voltage regulating module, a second voltage regulating module, a voltage feedback module and an upper computer, the first voltage regulating module, the second voltage regulating module, the voltage feedback module and the first voltage regulating module are connected in sequence, the upper computer is connected with the first voltage regulating module, the second voltage regulating module is used for outputting low-noise target power voltage,

[0029] The second voltage regulating module includes a voltage regulating chip U2, a resistor R6, a resistor R7, a capacitor C2, a capacitor C3, a capacitor C4 and a capacitor C5.

[0030] The capacitor C2 and the capacitor C3 are connected in parallel, one end is grounded, and the other end is connected with the pins 6, 7 and 8 of the voltage regulating chip U2, the first voltage regulating module and the voltage feedback module, one end of the capacitor C4 is connected with the pin 5 of the voltage regulating chip U2, and the other end is grounded.

[0031] The pins 1 and 2 of the voltage regulating chip U2 are connected with one end of the resistor R6, one end of the capacitor C5 and the voltage feedback module, the pin 3 is connected with the other end of the resistor R6, the other end of the capacitor C5 and one end of the resistor R7, and the other end of the resistor R7 is connected with the pin 4 of the voltage regulating chip U2 and grounded.

[0032] The primary voltage regulation module comprises a voltage regulation chip U1, an inductor L1, a resistor R1 and a capacitor C1; the inductor L1 is used for energy storage, cooperates with a MOS tube inside the voltage regulation chip U1, can realize charging and discharging, and achieves the purpose of adjusting the output voltage; the resistor R1 serves as a pull-down resistor of VCCADJ_EN, pulls down the level in the power-on stage, can keep the voltage regulation chip U1 in the enabled state in the power-on stage, has no voltage output, and can start the work of the voltage regulation chip U1 by pulling up the level of VCCADJ_EN of the host computer; the capacitor C1 and the capacitor C2 serve as filter capacitors, filter the voltage, and reduce the power supply ripple; the resistor R6 and the resistor R7 are used for adjusting the output voltage of the voltage regulation chip U2; the pins 7 and 8 of the voltage regulation chip U2 are connected with the pin 7 of the voltage regulation chip U1, and the work of the voltage regulation chip U2 is started synchronously after the voltage regulation chip U1 enables the output; the voltage regulation chip U1 is used for voltage boosting and voltage reducing, the voltage regulation chip 2 is used for stabilizing the voltage output and reducing the power supply ripple, in the specific implementation, as long as a power supply chip capable of realizing the function is selected from the prior art, and the type is not limited, for example, SW6301V of I smartware and IP2363 of Injoinic, and the control program is well known to those skilled in the art, which is obtained without creative labor of those skilled in the art;

[0033] The pin 1 of the voltage regulation chip U1 is connected with the capacitor C1, the pin 2 is connected with the resistor R1 and the host computer, the pin 4 is connected with one end of the inductor L1, the pin 5 is connected with the other end of the inductor L1, the pins 6 and 9 are grounded, the pin 7 is connected with one end of the capacitor C2, one end of the capacitor C3, the pins 6, 7 and 8 of the voltage regulation chip U2 and the voltage feedback module, and the pin 8 is connected with the voltage feedback module.

[0034] The voltage feedback module comprises a resistor R2, a resistor R3, a resistor R4 and a resistor R5; the resistor R2, the resistor R3, the resistor R4 and the resistor R5 are used for adjusting the output voltage of the voltage regulation chip U1.

[0035] One end of the resistor R2 is connected with the primary voltage regulation module, the other end is connected with one end of the resistor R3, one end of the resistor R4 and one end of the resistor R5; the other end of the resistor R3 is connected with the primary voltage regulation module; the other end of the resistor R4 is grounded; and the other end of the resistor R5 is connected with the pins 1 and 2 of the voltage regulation chip U2.

[0036] The working principle of the utility model is as follows:

[0037] The host computer sets an output target voltage value and sends it to the voltage regulating chip U1, and enables the voltage regulating chip U1 through VCCADJ_EN, the voltage regulating chip U1 performs voltage regulation on the input 3.3V voltage, and outputs a first output voltage value to the voltage regulating chip U2, and the voltage regulating chip U2 performs voltage regulation on the input first output voltage value, and outputs a second output voltage value.

[0038] The voltage feedback module collects the actual output voltage value of the voltage regulating chip U2 and feeds it back to the voltage regulating chip U1, and the voltage regulating chip U1 compares the output target voltage value and the actual output voltage value to dynamically adjust the output first output voltage value, and further dynamically adjust the output second output voltage value, so that the second output voltage value is infinitely close to the output target voltage value.

[0039] In summary, the utility model has the advantages that:

[0040] By setting a first voltage regulating module, a second voltage regulating module and a voltage feedback module, and sequentially connecting the first voltage regulating module, the second voltage regulating module, the voltage feedback module and the first voltage regulating module, the voltage regulating chip U1 of the first voltage regulating module has the functions of voltage boosting and voltage reducing, can meet the requirements of voltage boosting and voltage reducing on the basis of the voltage drop of the voltage regulating chip U2 of the second voltage regulating module, does not need to use different power supply chips for processing, reduces the types of chip materials, and also reduces the number of occupied IO resources of the host computer; the voltage feedback module collects the second output voltage of the second voltage regulating module and feeds it back to the first voltage regulating module, so that the first voltage regulating module can dynamically adjust the first output voltage, without keeping the first output voltage with sufficient margin as in the prior art, effectively reducing the voltage difference of the voltage regulating chip U2 of the second voltage regulating module, reducing the heat dissipation of the voltage regulating chip U2, greatly reducing the power consumption and cost of the low-noise power supply circuit, and also improving the overcurrent capacity of the voltage regulating chip U2, reducing the power consumption and cost of the entire low-noise power supply circuit.

[0041] Although the specific embodiments of the utility model are described above, those skilled in the art should understand that the specific examples described are only illustrative, and are not used to limit the scope of the utility model, and equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the utility model should be covered within the scope of protection of the claims of the utility model.

Claims

1. A low noise power supply circuit for an optical module, characterized by: It includes a primary voltage regulating module, a secondary voltage regulating module, a voltage feedback module and a host computer; the primary voltage regulating module, the secondary voltage regulating module, the voltage feedback module and the primary voltage regulating module are connected in sequence; the host computer is connected with the primary voltage regulating module; The secondary voltage regulating module includes a voltage regulating chip U2, a resistor R6, a resistor R7, a capacitor C2, a capacitor C3, a capacitor C4 and a capacitor C5; One end of the capacitor C2 and the capacitor C3 is grounded, and the other end is connected with the pin 6, 7 and 8 of the voltage regulating chip U2, the primary voltage regulating module and the voltage feedback module; one end of the capacitor C4 is connected with the pin 5 of the voltage regulating chip U2, and the other end is grounded; The pin 1 and 2 of the voltage regulating chip U2 are connected with one end of the resistor R6, one end of the capacitor C5 and the voltage feedback module, and the pin 3 is connected with the other end of the resistor R6, the other end of the capacitor C5 and one end of the resistor R7; the other end of the resistor R7 is connected with the pin 4 of the voltage regulating chip U2 and grounded.

2. A low noise power supply circuit for an optical module as recited in claim 1, wherein: The primary voltage regulating module includes a voltage regulating chip U1, an inductor L1, a resistor R1 and a capacitor C1; The pin 1 of the voltage regulating chip U1 is connected with the capacitor C1, the pin 2 is connected with the resistor R1 and the host computer, the pin 4 is connected with one end of the inductor L1, the pin 5 is connected with the other end of the inductor L1, the pin 6 and 9 are grounded, the pin 7 is connected with one end of the capacitor C2, one end of the capacitor C3, the pin 6, 7 and 8 of the voltage regulating chip U2 and the voltage feedback module, and the pin 8 is connected with the voltage feedback module.

3. A low noise power supply circuit for an optical module as recited in claim 1, wherein: The voltage feedback module includes a resistor R2, a resistor R3, a resistor R4 and a resistor R5; One end of the resistor R2 is connected with the primary voltage regulating module, and the other end is connected with one end of the resistor R3, one end of the resistor R4 and one end of the resistor R5; the other end of the resistor R3 is connected with the primary voltage regulating module; the other end of the resistor R4 is grounded; the other end of the resistor R5 is connected with the pin 1 and 2 of the voltage regulating chip U2.

Images