Miniature High Efficiency Switching Boost/Buck Module

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Miniature High Efficiency Switching Boost/Buck Module [Copy link]

1. Small adjustable switch boost module VS1 The VS1 high-efficiency adjustable boost module uses a high-speed switching circuit inside to boost the voltage. It has the characteristics of small size, low power consumption, large output current and strong function. It can be applied to various circuits that require boosting and high stability, solving the limitations of product design caused by the size and weight of the battery.

The performance indicators are shown in the following table:

Input voltage	2.5～40V
Output voltage	2.5～40V
Static power consumption	4mA
Output voltage mode	Continuously adjustable
Output Power	1.25W
Operating frequency	50~100KHz
Output ripple	40mV
Automatic voltage stabilization function	have
Operating temperature	-20°C~+75°C
Module volume	12×22×32mm

Practical application example: Multimeter stacked battery replaces

multimeter, which is an essential tool for electronics workers. Its high resistance range usually uses a 9V, 15V or 22.5V stacked battery. This battery is not only expensive, but also short-lived, and frequent replacement is not economical.
At present, newspapers and magazines often introduce boost circuits for multimeters, which are generally composed of triodes and boost transformers. Electronic enthusiasts often worry about how to make boost transformers during the self-made process. Moreover, the efficiency of this circuit will change with the selected components and manufacturing process, which is difficult for electronics enthusiasts with less manufacturing experience.

The volume of the adjustable DC boost module is: 12x22x32 mm, and the pin distribution is shown in Figure 1. Pin 1 is the input positive power supply, pin 2 is the ground, pin 3 is the output positive power supply, and pins 5 and 4 are the output voltage adjustment terminals. A 100K variable resistor VR can be connected externally to adjust the output voltage. The input voltage range of the module is 2.5~40V. After boosting, it can output 3~40V DC voltage. The working efficiency of the circuit is greater than 85%. The following figure is a typical application diagram of the boost module:

Connect the peripheral components according to Figure 2, and it will work normally after power on. Adjust the 100K variable resistor VR to get any value within the rated output voltage range. When the resistance of VR is 15K, the module's regulated output voltage is 10V. After adjustment, seal VR with insulating paint and connect it to the load. This module can be used to make a small-power portable adjustable power supply.

Note: In addition to the control chip, the boost module also contains other components such as Schottky rectifier components and imported special materials high-efficiency boost inductors. 10uf/50v electrolytic capacitors are set at the input and output ends as filters. When using, it should be connected as required, and it cannot be connected incorrectly. And pay attention to two points:

1. The external voltage adjustment resistor should be connected before the module is powered on, because when pin 6 is left floating, the output will be the highest voltage, which may damage the load, and a short circuit between pin 6 and the output ground will cause permanent damage to the boost module.
2. The boost module can only be used for boosting, that is, the input voltage must be lower than the output voltage.

2. Ultra-miniature high-efficiency boost device V2 With the development of electronic technology, various portable electronic products have developed rapidly, and the development trend is to have stronger functions, smaller size, lighter weight, and less power consumption. When the volume of the product is required to be very small, the contradiction between the volume and weight of the battery part becomes very prominent. The operating voltage of most circuits is between 3 and 6 volts. At this time, a boost circuit can be used to reduce the number and volume of batteries, so as to achieve the purpose of designing products at will.

Input voltage: 1V-5VOutput
current: 20mA at 1.5V, 100mA at 2.4V, 200mA at 3V, 350mA at 4.5VQuiet
current: 350uA at 1.5V, 200uA at 2.4V, 100uA at 3V, 50uA at 4.5VOperating
frequency: 100KHzOperating
temperature: -40℃to+85℃.Ripple
coefficient: Typical 40mA (PP)
Volume: 10×20×6mm

V2 is a miniature high-efficiency boost device with a volume of only 20x10x6 mm. It has an input voltage of 1 to 5 volts and outputs a stable 5 volt DC voltage. Its conversion efficiency is greater than 85%, and it can work safely at an ambient temperature of -45 to +85 degrees. Its outstanding advantage is that it consumes very little power. The quiescent current is related to the input voltage. The higher the voltage, the less power it consumes. When the input voltage is 1.2 volts, the quiescent current is 370 microamperes, when the input voltage is 2.4 volts, it is 200 microamperes, when the input voltage is 3 volts, it is 100 microamperes, and when the input voltage is 4.5 volts, it is only 50 microamperes.

The relationship between

V2 input voltage and output current is shown in Table 1, the relationship between quiescent current and input voltage is shown in Table 2, the relationship between conversion efficiency and input voltage and output current is shown in Table 3, and the relationship between output ripple coefficient and input voltage and output current is shown in Table 4. VO is the 5V voltage output terminal, G is the ground terminal, VI is the power input terminal, and the internal structure is shown in the right figure: The internal operating frequency of V2 is 100KHZ, and the output current is related to the input voltage. The higher the input voltage, the greater the output current. When the input voltage is 1.2V, the output current is 18mA, when the input voltage is 2.4V, the output current is 100mA, when the input voltage is 3V, the output current is 200mA, and when the input voltage is 4.5V, the output current is 350mA.

V2 contains two input and output filter tantalum capacitors. It can work without any external components. The ripple factor of the output voltage is 40 millivolts peak-to-peak. If the circuit has special needs to reduce the ripple factor of the output voltage, you can add a 47-100 microfarad electrolytic capacitor and a 104 picofarad high-frequency ceramic capacitor to the input and output ends, or add a filter inductor of about 1 microhenry and a filter capacitor of 100 microfarad to the output circuit to get a better voltage stabilization effect. After using V2, only one or two batteries can provide a stable voltage of 5 volts.

3. Small and efficient step-down 5V module

The switching buck device is equivalent to the current 7800 series regulator in function, but the performance is different. The efficiency of the 7800 series is less than 50%, while the switching regulator is higher than 80%, which reduces the cost of the front-end power supply. When in use, the heat sink required by the 7800 series is not required at the same power, saving circuit board space.

Maximum input voltage	40V
Minimum input voltage	3V
Maximum output current	500mA
Static power consumption	3mA
Switching frequency	100KHZ
Output voltage ripple	100mVp-p
Work efficiency	80%
Operating temperature	0℃~70℃
Dimensions	12x22x32mm

　

Pin function: P1, input terminal; P2, ground; P3, output terminal; Pin pitch: 5.08 mm.

Due to the high integration of the device, the peripheral circuit is very simple. It only needs to connect an electrolytic capacitor to the front and rear stages, as shown in Figure 2. The value of the capacitor is related to the output current and output voltage ripple. The values of C1 and C2 in the circuit have a great influence on the output current and output voltage ripple. The larger the value, the larger the output current and the smaller the ripple coefficient. Therefore, if space permits, the values of C1 and C2 should be increased, generally between 10μ~1000μ, and the capacitor withstand voltage is 1.5 times the operating voltage.

Device Performance	7806	Three-terminal switching regulator
Output voltage	6V	6V
Static power consumption	4.2 mA	2.5 mA
After connecting the load
Input Current	147 mA	90 mA
Output Current	139 mA	139 mA
Work efficiency	50%	80%

The performance comparison between the switching regulator and the 7800 series three-terminal regulator is shown in Figure 3, and the experimental results are shown in the table above.

4. Small and efficient switching step-down 3.3V output module

This one is very similar to the 5V output, but without the case and smaller in size (28x18x10mm)