Vehicle steering lamp driving circuit with reference voltage

Abstract

The utility model discloses a reference voltage vehicle turn light drive circuit, which comprises a programmable reference voltage generating circuit PVG, the programmable reference voltage generating circuit PVG comprises a bit code controller ADC, a programmable current source and a variable resistor R1, the bit code controller ADC controls the programmable current source to generate corresponding reference current according to acquired power supply voltage VDDH, and the variable resistor R1 is connected with the programmable current source. A reference current flows through a variable resistor R1 to generate a reference voltage VCOMP, the relation between the reference voltage VCOMP and a power supply voltage VDDH is preset, when the power supply voltage of the steering lamp fluctuates, the magnitude of the current output by a programmable current source is controlled through a bit code controller ADC, so that the slope of the reference voltage VCOMP changing along with the power supply voltage VDDH is controlled, and the steering lamp is controlled to be in a stable state. And the driver is prevented from giving wrong load judgment.

Description

Technical Field

[0001] The utility model relates to a turn signal driving circuit, in particular to a turn signal driving circuit with a variable reference voltage. Background Art

[0002] Turn signal lights on motorcycles and electric vehicles can be damaged or experience connection failures, posing safety hazards. Therefore, turn signal drivers must monitor load conditions in real time and provide a fault indication by changing the flashing frequency when a turn signal malfunctions. Typically, turn signal drivers compare the voltage across a sampling resistor with a reference voltage and use the comparison result to determine the turn signal status. However, the power supply voltage (battery voltage) of motorcycles and electric vehicles fluctuates within a certain range, causing the turn signal power supply voltage to also fluctuate within a certain range. Consequently, the turn signal current also fluctuates with the power supply voltage. If the reference voltage is uncorrelated with the power supply voltage, the driver may misjudge the load and incorrectly change the flashing frequency. To avoid this error, the reference voltage must be compensated for its correlation with the power supply voltage. Since there are many different types of turn signal lights, and their current varies with power supply voltage, this power supply voltage compensation coefficient must be programmable to accommodate diverse application scenarios. Utility Model Content

[0003] In order to overcome the deficiencies of the prior art, the utility model provides a vehicle turn signal driving circuit with a reference voltage.

[0004] The technical solution adopted by the utility model to solve its technical problems is:

[0005] A vehicle turn signal driving circuit with a reference voltage, comprising:

[0006] Programmable reference voltage generator PVG: input terminal connected to power supply voltage V DDH and reference voltage V REF , the output terminal is based on the power supply voltage V DDH and reference voltage V REF Output reference voltage V COMP .

[0007] sampling resistor R CS : Connected in series in the turn signal L1 load circuit to collect the sampling voltage V of the turn signal L1 load circuit CS .

[0008] Comparator COMP: one input terminal is connected to the reference voltage V COMP , the other input terminal is connected to the sampling voltage V CS .

[0009] Variable frequency drive circuit D f1 / f2:The input end is connected to the output end of the comparator COMP, the frequency conversion drive circuit D f1 / f2 The output end is connected to the MOS tube T1 of the turn signal lamp L1 load circuit, and the output frequency is f 1 or frequency f 2 driving signal to control the working state of the MOS tube T1. Usually, the f 2> f 1. Typical f 2=2 f 1.

[0010] The programmable reference voltage generating circuit PVG includes a bit code controller ADC, a current source I, a variable resistor R 1 and resistor R 2 are connected in series to form a variable voltage sampling branch, which is composed of a converter VI and a resistor R 3 constituted by a reference voltage sampling circuit and a programmable current source composed of at least two current source branches connected in parallel; each of the current source branches is provided with a switch unit; the input terminal of the bit code controller ADC is connected to the power supply voltage V DDH and reference voltage V REF The output end outputs a multi-channel control signal corresponding to the switch unit to control the working state of the switch unit, and one end of the variable voltage sampling branch is connected to the working voltage V DD , the other end is grounded; the input end of the programmable current source is connected to the operating voltage V DD , the output terminal is connected to the variable resistor R 1 and resistor R 2, one end of the reference voltage sampling circuit is connected to the current source I and the variable resistor R 1, the other end is grounded, the converter VI and the resistor R The contact of 3 is the reference voltage V COMP Connected to the comparator COMP.

[0011] The reference voltage V COMP With the supply voltage V DDH The relationship is pre-set, which is set according to the volt-ampere characteristic curve of the turn signal lamp L1. COMP With the supply voltage V DDH The relationship between the variable resistor R A resistance value of 1 is sufficient.

[0012] The beneficial effect of the present invention is that when the power supply voltage of the turn signal lamp fluctuates, the programmable reference voltage generating circuit of the present invention can generate a reference voltage according to the input reference voltage V REF With the power supply voltage V DDH, the current output by the programmable current source is controlled by the bit code controller ADC, thereby controlling the reference voltage V COMP With the power supply voltage V DDH The change slope of the turn signal driver makes the sampling voltage V CS With reference voltage V COMP After comparison, the correct result is output to avoid the driver making an incorrect load judgment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0014] Figure 1 It is a circuit principle diagram of the utility model.

[0015] Figure 2 This is a circuit diagram of a programmable reference voltage generator circuit PVG. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be noted that the embodiments of the present invention and the features therein can be combined with each other unless there is any conflict.

[0017] It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention.

[0018] Reference Figure 1 and Figure 2 A reference voltage vehicle turn signal driving circuit includes: a programmable reference voltage generating circuit PVG, the programmable reference voltage generating circuit PVG includes a bit code controller ADC, a programmable current source and a variable resistor R 1. The bit code controller ADC collects the power supply voltage V DDH Control the programmable current source to generate a corresponding reference current, which flows through the variable resistor R 1Generate reference voltage V COMP , the reference voltage V COMP With the supply voltage V DDH The relationship is pre-set, which is set according to the volt-ampere characteristic curve of the turn signal L1. R The resistance value of 1 is pre-set to the intersection of the reference voltage with different power supply compensation coefficients and the power supply voltage change curve. For example, the intersection point can be set near the typical power supply voltage. When producing the driver, the required variable resistor is determined according to the volt-ampere characteristics of the turn signal. R 1 resistance, according to the reference voltage V COMP With the supply voltage V DDHThe relationship between the variable resistor R A resistance of 1 is sufficient, a variable resistor R 1 can be an adjustable resistor, which is achieved by adjusting the resistance value, or a fixed resistor, which is achieved by replacing resistors of different resistance values, so that reference voltages with different power supply compensation coefficients can maintain consistent voltage values near the typical power supply voltage, simplifying application settings and improving development efficiency.

[0019] The input terminal of the programmable reference voltage generating circuit PVG is connected to the reference voltage V REF and the power supply voltage V DDH , the output terminal is based on the power supply voltage V DDH and reference voltage V REF Output reference voltage V COMP The sampling resistor R CS Connected in series in the turn signal L1 load circuit to collect the sample voltage V of the turn signal L1 load circuit CS An input terminal of the comparator COMP is connected to the reference voltage V COMP , the other input terminal is connected to the sampling voltage V CS .

[0020] The variable frequency drive circuit D f1 / f2 The input terminal is connected to the output terminal of the comparator COMP, and the variable frequency drive circuit D f1 / f2 The output end is connected to the MOS tube T1 in the load circuit of the turn signal L1, and the output frequency is f 1 or frequency f 2 driving signal to control the working state of the MOS tube T1. f 2> f 1. Typical f 2=2 f 1.

[0021] The current source I, the variable resistor R 1 and resistor R 2 are connected in series to form a variable voltage sampling branch, the converter VI and the resistor R 3 are connected in series to form a reference voltage sampling circuit, the programmable current source is composed of at least two current source branches connected in parallel, and each of the current source branches is provided with a switch unit; the output end of the bit code controller ADC outputs a multi-channel control signal corresponding to the switch unit to control the working state of the switch unit in each current source branch, and one end of the variable voltage sampling branch is connected to the working voltage V DD , the other end is grounded; the input end of the programmable current source is connected to the operating voltage V DD , the output terminal is connected to the variable resistor R 1 and resistor R2, one end of the reference voltage sampling circuit is connected to the current source I and the variable resistor R 1, the other end is grounded, the converter VI and the resistor R The contact point 3 is the reference voltage V COMP .

[0022] like Figure 2 As shown in FIG, the programmable current source is composed of a current source I1 connected in series with a switch unit S1, a current source I2 connected in series with a switch unit S2, and a current source I n Connect the corresponding switch unit S in series n The current source I1~In is formed by connecting n current source branches in parallel. The size of the current source I1~In is preset by the user through multiple bits. The setting value is related to the relationship between the current of the lamp and the change of the power supply voltage. The bit code controller ADC output is connected to the switch unit S1, switch unit S2 to switch unit S n The multi-channel control signal controls the switch unit S1, the switch unit S2 to the switch unit S n In the 0 (off) or 1 (on) position, N switching units can be combined in various ways to achieve a programmable output current.

[0023] When the turn signal lamp is working normally, the sampling voltage V CS Greater than the reference voltage V COMP , the comparator COMP outputs a low level, the variable frequency drive circuit D f1 / f2 The output signal frequency is f 1. When the turn signal fails, the sampling voltage V CS The comparator COMP outputs a high level, and the frequency of the signal output by the variable frequency drive circuit is f 2. The flashing frequency of the turn signal changes.

[0024] When the power supply voltage of the turn signal lamp fluctuates, the programmable reference voltage generating circuit can generate a reference voltage according to the reference voltage V REF With the power supply voltage V DDH , the current output by the programmable current source is controlled by the bit code controller ADC, thereby controlling the reference voltage V COMP With the power supply voltage V DDH The change slope of the turn signal driver makes the sampling voltage V CS With reference voltage V COMP After comparison, the correct result is output to avoid the driver making an incorrect load judgment.

[0025] In this utility model, the term "plurality" refers to two or more, unless otherwise expressly defined. The term "and / or" as used herein includes any and all combinations of one or more of the relevant listed items. Terms such as "install," "connect," "connect," and "fix" should be understood broadly. For example, "connect" can mean a fixed connection, a detachable connection, or an integral connection; "connected" can mean a direct connection or an indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances.

[0026] It should be noted that when an element is referred to as being "assembled to," "mounted to," "fixed to," or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0027] Throughout this specification, terms such as "one embodiment," "some embodiments," or "specific embodiments" mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, illustrative uses of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0028] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and purpose of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A reference voltage vehicle turn signal driving circuit, characterized in that The programmable reference voltage generating circuit PVG includes a bit code controller ADC, a programmable current source and a variable resistor. R 1. The bit code controller ADC collects the power supply voltage V DDH Control the programmable current source to generate a corresponding reference current, which flows through the variable resistor R 1Generate reference voltage V COMP , the reference voltage V COMP With the supply voltage V DDH The relationship is pre-set.

2. The vehicle turn signal driving circuit with reference voltage according to claim 1, characterized in that The input terminal of the programmable reference voltage generating circuit PVG is connected to the reference voltage V REF and the power supply voltage V DDH , the output terminal is based on the power supply voltage V DDH and reference voltage V REF Output reference voltage V COMP .

3. The reference voltage vehicle turn signal driving circuit according to claim 2, characterized in that Also includes sampling resistor R CS , the sampling resistor R CS Connected in series in the turn signal L1 load circuit to collect the sample voltage V of the turn signal L1 load circuit CS .

4. The reference voltage vehicle turn signal driving circuit according to claim 3, characterized in that The comparator COMP is further included, wherein an input terminal of the comparator COMP is connected to the reference voltage V COMP , the other input terminal is connected to the sampling voltage V CS .

5. The vehicle turn signal driving circuit with reference voltage according to claim 4, characterized in that Also includes variable frequency drive circuit D f1 / f2 , the variable frequency drive circuit D f1 / f2 The input terminal is connected to the output terminal of the comparator COMP, and the variable frequency drive circuit D f1 / f2 The output end is connected to the MOS tube T1 in the load circuit of the turn signal L1, and the output frequency is f 1 or frequency f 2 driving signal to control the working state of the MOS tube T1.

6. The vehicle turn signal driving circuit with reference voltage according to claim 5, characterized in that Also current source I, resistor R 2. Converter VI and resistor R 3. The current source I and the variable resistor R 1 and resistor R 2 are connected in series to form a variable voltage sampling branch, the converter VI and the resistor R 3 are connected in series to form a reference voltage sampling circuit, the programmable current source is composed of at least two current source branches connected in parallel, and each of the current source branches is provided with a switch unit; the output end of the bit code controller ADC outputs a multi-channel control signal corresponding to the switch unit to control the working state of the switch unit in each current source branch, and one end of the variable voltage sampling branch is connected to the working voltage V DD , the other end is grounded; the input end of the programmable current source is connected to the operating voltage V DD , the output terminal is connected to the variable resistor R 1 and resistor R 2, one end of the reference voltage sampling circuit is connected to the current source I and the variable resistor R 1, the other end is grounded, the converter VI and the resistor R The contact point 3 is the reference voltage V COMP .

7. The vehicle turn signal driving circuit with reference voltage according to claim 5, characterized in that described f 2> f 1.

8. The vehicle turn signal driving circuit with reference voltage according to claim 5, characterized in that described f 2=2 f 1.

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