поискавой системы для электроныых деталей |
|
STOD2540PMR датащи(PDF) 8 Page - STMicroelectronics |
|
STOD2540PMR датащи(HTML) 8 Page - STMicroelectronics |
8 / 19 page Functional description STOD2540 8/19 5 Functional description 5.1 Boost controller STOD2540 is a boost converter operating in PFM (pulsed frequency modulation) mode. The converter monitors the output voltage through the bridge resistor divider R1 and R2 and when the feedback voltage falls below the reference voltage, REF2, the boost switch tSW turns ON and the current ramps up. The inductor current is measured by detect the temperature compensated drain voltage of the boost MOSFET. The boost turns off when its drain voltage reaches the reference REF1, the main switch remains off until the minimum off time (300ns typical) has passed and the feedback voltage is below the reference again. A maximum ON time of 4µs prevent the switch tSW to stay ON during a too long period of time. In order to well calculate the bridge resistors values with a fixed VO, the following formula can be used: 5.2 Adjustable peak inductor current limit The peak inductor current is monitored by sensing the drain voltage of the switch tSW. Since it exceeds the temperature compensated and supply voltage compensated reference REF1, the RS Flip flop is reset and tSW is turned OFF. By connecting a resistance between the pin RSET and GND, the peak current limit can be adjusted from 200mA to 1.1A (RSET from 10kΩ to 100kΩ). When the pin RSET is directly connected to VI, the default value is 1A. 5.3 Enable The ENABLE pin is a high logic input signal and allows turning on/off the controller without cutting the input voltage from the boost regulator circuit. With a high input voltage (1.2V <VEN< VI+0.3V) on this pin, the device is allowed to work normally. No pull-up or pull down is present on this pin. 5.4 OVP If the regulation loop is cut, there is no signal at the feedback pin, the PFM controller will then continue to switch without control and generate an output voltage at the SW, VCAP and VO pin exceeding the breakdown value VBSW, VBCAP and VBO. The Over Voltage Protection (OVP) senses the voltage at the VCAP pin.When the voltage exceed the breakdown voltage of the device the controller is automatically turned Off. A hysteresis control enables the device to automatically restart when the output voltage drops below a 2V typical value. |
Аналогичный номер детали - STOD2540PMR |
|
Аналогичное описание - STOD2540PMR |
|
|
ссылки URL |
Конфиденциальность |
ALLDATASHEETRU.COM |
Вашему бизинису помогли Аллдатащит? [ DONATE ] |
Что такое Аллдатащит | реклама | контакт | Конфиденциальность | обмен ссыками | поиск по производителю All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |