1.Uz - Stable voltage
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Refers to the stable voltage value generated at both ends of the regulator tube when it passes the rated current. The value varies slightly with the operating current and temperature. Due to the difference in manufacturing process, the pressure regulator value of the same type of regulator tube is not completely consistent. For example, the 2CW51 voltage regulator has a Vzmin of 3.0V and a Vzmax of 3.6V.
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2.Iz - Rated current
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Refers to the current value passing through the regulator tube when it produces a stable voltage. Lower than this value, although the pressure regulator is not unable to stabilize the pressure, but the stabilizing effect will become worse; Higher than this value, as long as the rated power loss is not exceeded, it is also allowed, and the voltage regulator performance will be better, but it will consume more power.
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3.Rz - Dynamic resistance
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The ratio of voltage change to current change at both ends of a regulator tube. The ratio varies with the working current, generally the greater the working current, the smaller the dynamic resistance. For example, when the operating current of the 2CW7C regulator is 5mA, the Rz is 18Ω; When the working current is 1OmA, the Rz is 8Ω. For 20mA, Rz is 2Ω. > At 20mA, this value is basically maintained.
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4.Pz - Rated power consumption
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It is determined by the allowable temperature rise of the chip and its value is the product of the stable voltage Vz and the maximum allowable current Izm. For example, the Vz of the 2CW51 regulator tube is 3V and the Izm is 20mA, so the Pz of the tube is 60mWo
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5. α - temperature coefficient
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If the temperature of the regulator tube changes, its stable voltage will also change slightly, and the relative change in the voltage at both ends of the tube caused by the temperature change of 1 ° C is the temperature coefficient (unit: %\/ ° C).
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Generally speaking, the voltage regulator value below 6V belongs to Zener breakdown, and the temperature coefficient is negative; For avalanche breakdown above 6V, the temperature coefficient is positive. When the temperature increases, the depletion layer decreases. In the depletion layer, the valence electrons of the atom rise to a higher energy, and the smaller electric field strength can excite the valence electrons from the atom to produce Zener breakdown, so the temperature coefficient is negative.
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Avalanche breakdown occurs when the depletion layer is wide and the electric field intensity is low, and the increase of temperature increases the vibration amplitude of lattice atoms, which hinders the movement of charge carriers. In this case, only by increasing the reverse voltage can avalanche breakdown occur, so the voltage temperature coefficient of avalanche breakdown is positive. This is why the stable value of a 15V voltage regulator increases gradually with temperature, while the stable value of a 5V voltage regulator decreases gradually with temperature. For example, the temperature coefficient of the 2CW58 pressure regulator is 0.07%\/°C, that is, for every 1°C increase in temperature, its pressure regulator value will increase by 0.07%.
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In cases where the power supply is required to be relatively high, two regulator tubes with opposite temperature coefficients can be connected in series as compensation. Due to mutual compensation, the temperature coefficient is greatly reduced, so that the temperature coefficient can reach 0.0005%\/℃.
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6.IR - Reverse leakage current
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Refers to the leakage current generated by the voltage regulator diode under the specified reverse voltage. For example, when VR=1V of a 2CW58 regulator, IR=O.1uA; When VR=6V, IR=10uA.