Electronic Components Datasheet Search |
|
LM5000-3MTCEP Datasheet(PDF) 10 Page - National Semiconductor (TI) |
|
|
LM5000-3MTCEP Datasheet(HTML) 10 Page - National Semiconductor (TI) |
10 / 18 page Block Diagram 20098303 Boost Regulator Operation The LM5000EP utilizes a PWM control scheme to regulate the output voltage over all load conditions. The operation can best be understood referring to the block diagram and Figure 3. At the start of each cycle, the oscillator sets the driver logic and turns on the NMOS power device conducting current through the inductor, cycle 1 of Figure 3 (a). During this cycle, the voltage at the COMP pin controls the peak inductor current. The COMP voltage will increase with larger loads and decrease with smaller. This voltage is compared with the summation of the SW volatge and the ramp com- pensation.The ramp compensation is used in PWM architec- tures to eliminate the sub-harmonic oscillations that occur during duty cycles greater than 50%. Once the summation of the ramp compensation and switch voltage equals the COMP voltage, the PWM comparator resets the driver logic turning off the NMOS power device. The inductor current then flows through the output diode to the load and output capacitor, cycle 2 of Figure 3 (b). The NMOS power device is then set by the oscillator at the end of the period and current flows through the inductor once again. The LM5000EP has dedicated protection circuitry running during the normal operation to protect the IC. The Thermal Shutdown circuitry turns off the NMOS power device when the die temperature reaches excessive levels. The UVP comparator protects the NMOS power device during supply power startup and shutdown to prevent operation at voltages less than the minimum input voltage. The OVP comparator is used to prevent the output voltage from rising at no loads allowing full PWM operation over all load conditions. The LM5000EP also features a shutdown mode. An external capacitor sets the softstart time by limiting the error amp output range, as the capacitor charges up via an internal 10µA current source. The LM5000EP is available in two operating frequency ranges. The LM5000-3EP is pin selectable for either 300kHz (FS Grounded) or 700kHz (FS Open). The LM5000-6EP is pin selectable for either 600kHz (FS Grounded) or 1.3MHz (FS Open) www.national.com 10 |
Similar Part No. - LM5000-3MTCEP |
|
Similar Description - LM5000-3MTCEP |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |