一种应用于小黑盒的LDO输出扩流电路
By controlling the opening and closing of the field-effect transistor Q1 through the voltage comparator U1 and the Zener diode D1, the problems of high power consumption of resistors and strict load current requirements in the prior art are solved, and stable LDO output current amplification is achieved, thereby improving circuit efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 上海奥特普实业有限公司
- Filing Date
- 2025-10-11
- Publication Date
- 2026-07-17
AI Technical Summary
Existing technologies control the conduction and cutoff of transistors by the voltage drop across the input resistor to achieve LDO output current amplification. However, this approach suffers from high resistor power consumption or strict load current requirements, and cannot achieve stable current amplification under different load current conditions.
The input voltage is controlled by a voltage comparator U1 and a Zener diode D1. Stable current amplification is achieved by turning on or off the field-effect transistor Q1, thus avoiding the problem of high power consumption of resistors.
Stable LDO output current amplification under different load current conditions was achieved, reducing resistor power consumption and improving circuit efficiency.
Smart Images
Figure CN224519203U_ABST
Abstract
Claims
1. An LDO output current expansion circuit applied to a small black box, characterized in that, include: The LDO chip has its input terminal electrically connected to the input power supply Vin, and its output terminal electrically connected to the output power supply Vldo. The input power supply Vin is electrically connected to a Zener diode D1. The chip also includes a voltage comparator U1 and a field-effect transistor Q1. The drain of the field-effect transistor Q1 is electrically connected to the input power supply Vin, and the source of the field-effect transistor Q1 is electrically connected to the output power supply Vldo. The positive input terminal of the voltage comparator U1 is electrically connected to the Zener diode D1, the negative input terminal of the voltage comparator U1 is electrically connected to the source of the field-effect transistor Q1, and the output terminal of the voltage comparator U1 is electrically connected to the gate of the field-effect transistor Q1.
2. The LDO output current expansion circuit applied to a small black box according to claim 1, characterized in that, A resistor R1 is electrically connected between the output of voltage comparator U1 and the gate of field-effect transistor Q1.
3. The LDO output current expansion circuit applied to a small black box according to claim 2, characterized in that, A resistor R2 is electrically connected between resistor R1 and the gate of field-effect transistor Q1.
4. The LDO output current expansion circuit applied to a small black box according to claim 3, characterized in that, Resistor R2 is grounded.
5. The LDO output current expansion circuit applied to a small black box according to claim 1 or 2 or 3, characterized in that, The voltage comparator U1 is electrically connected to a DC power supply Vdd.
6. The LDO output current expansion circuit applied to a small black box according to claim 5, characterized in that, Voltage comparator U1 has a grounded terminal.
7. An LDO output current amplification circuit for a small black box according to claim 1, 2, or 3, characterized in that, The source of the field-effect transistor Q1 is electrically connected to a resistor R3, which is grounded.
8. The LDO output current expansion circuit applied to a small black box according to claim 1 or 2 or 3, characterized in that, The LDO chip has a grounded pin.