STR5412 Datasheet – Hybrid Voltage Regulator – Sanken

STR5412 Datasheet PDF can download.

This is one of the Voltage Regulator types.

Manufacturers of the product is Sanken.

This is SIP 5 Pin Type.

Image and pinouts

STR5412 sanken

1. Input
2. Drive
3. Earth
4. Output
5. Control

Some of the text files within the PDF file

We are going to analyze the work of a switching power supply, which makes use of the STR5412 hybrid circuit. Firstly, we will describe what this hybrid circuit consists of, whose equivalent diagram can be seen in Figure 1. We can define its main concept as “a current switch in series configuration”, arranged between its pins 1 and 4; The switch is made up of a power transistor Q1. The base of Q1 is connected to pin 2 and through this the aforementioned element will be driven. In order to prevent Q1 from entering the conductive state, the circuit makes use of a second transistor Q3, whose activation allows the base polarization of Q1 to be short-circuited. In turn, the control of Q3 is governed by the presence of transistor Q2, which works configured as an error amplifier, whose emitter voltage is controlled by a zener diode – Dz – and its base circuit works by measuring or comparing the voltage of output through a resistive type work network. Pin 5, for its part, makes it possible to connect an external resistive network in order to modify the voltage level to be regulated. Figure 1.-

1. 112V 5A 40W
2. Switching Power Source, Voltage Regulator


Pinout and Circuits

STR5412 datasheet pdf

When the output voltage decreases, the conduction of the STR begins again, repeating the cycle already described. However, not everything is said, since the source is working at time intervals that may be different from that corresponding to the horizontal sweep trace, which can cause a certain instability – pulsating – in the output voltage. The solution consists, in this case, of synchronizing the operation of the power source, and to do so, use is made of a positive pulse extracted from the fly-back transformer, and which is applied to the base circuit of transistor Q1 via D807 and R805, so that every time the horizontal recoil pulse occurs, the STR hybrid starts driving, and then stops doing so once the corresponding working voltage is obtained. In other words, the STR5412 drives according to the energy requirement demanded by the fly-back, and also, during the recoil, the moment in which the brightness of the beam is extinguishing on the screen.

Please refer to the file for details.

BA5096 PDF Datasheet