Electronic Components Datasheet Search |
|
MAX5948A Datasheet(PDF) 11 Page - Maxim Integrated Products |
|
MAX5948A Datasheet(HTML) 11 Page - Maxim Integrated Products |
11 / 18 page -48V Hot-Swap Controllers with External RSENSE ______________________________________________________________________________________ 11 In the event of a short circuit at the output, the input supply may dip below the UV threshold, resetting the circuit breaker. The MAX5948 cycles ON and OFF until the short is removed, which can be minimized by creat- ing a deglitching delay at the UV pin with a capacitor from UV to VEE. This allows the input supply to recover before the UV pin resets the circuit breaker. Figure 10 shows a circuit that automatically resets the circuit breaker after a current fault. Transistors Q2 and Q3 along with C4, D1, R7, and R8 form a programma- ble one-shot circuit. In normal operation, the GATE pin is pulled high and Q3 is turned on, pulling node 2 to VEE. Resistor R8 turns off Q2. When a short occurs, the GATE pin is pulled low and Q3 turns off. Node 2 starts to charge C4 and Q2 turns on, pulling the UV pin low and resetting the circuit breaker. The instant C4 is fully charged, R8 turns off Q2, UV goes high and the GATE starts to ramp up. Q3 turns back on and pulls node 2 back to VEE. Diode D1 clamps node 3 at one diode drop below VEE. The duty cycle is set to 10% to prevent Q1 from overheating. Undervoltage and Overvoltage Protection The UV and OV pins can be used to detect undervolt- age and overvoltage conditions. The UV and OV pins are internally connected to analog comparators with 20mV of hysteresis. When the UV voltage falls below its threshold or the OV voltage rises above its threshold, the GATE pin is immediately pulled low. The GATE pin is held low until UV goes high and OV is low indicating that the input supply voltage is within specification. The UV pin is also used to reset the circuit breaker after a fault condition has occurred. The UV pin can be pulled below VUVL to reset the circuit breaker. VEE SENSE GATE DRAIN VDD OV UV PWRGD MAX5948A -48V RTN -48V RTN (SHORT PIN) * -48V *DIODES INC. SMAT70A. R4 562k Ω 1% R8 510k Ω 5% R5 19.1k Ω 1% R6 562k Ω 1% R7 1M Ω 5% R9 10k Ω 1% R1 0.02 Ω 5% R3 18k Ω 5% R2 10 Ω 5% C1 150nF 25V C4 1 µF 100V Q1 IRF530 D1 1N4148 Q2 2N2222 Q3 ZVN3310 C2 3.3nF 100V C3 100 µF 100V GATE 2V/div NODE2 50V/div 1s/div NODE 2 Figure 10. Automatic Restart After Current Fault |
Similar Part No. - MAX5948A |
|
Similar Description - MAX5948A |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | 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 |