 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
LTC4211CS8 Datasheet(PDF) 26 Page - Linear Technology |
|
|
|||||||||||||||||||||||||||||
LTC4211CS8 Datasheet(HTML) 26 Page - Linear Technology |
|
|
26 / 36 page  26 LTC4211 4211f APPLICATIO S I FOR ATIO Figure 17. 12V Hot Swap Application 12V Hot Swap Application Figure 17 shows a 12V, 3A hot swap application circuit. The resistor divider R1/R2 programs the undervoltage lockout externally and allows the system to start up after VCC increases above 9.46V. The resistor divider R3/R4 monitors VOUT and signals the RESET pin when VOUT goes above 10.54V. Transient voltage suppressor Z1 and snub- ber network (CX, RX) are highly recommended to protect the 12V applications system from ringing and voltage spikes. RG is recommended for VCC > 10V and it can minimize high frequency parasitic oscillations in the power MOSFET. AUTORETRY AFTER A FAULT To configure the LTC4211 to automatically retry after a fault condition, the FAULT and ON pins can be connected to a pull-up resistor (RAUTO) to the supply, as shown in FAULT VCC LTC4211MS SENSE GATE FB 1 2 3 4 5 10 RSENSE 0.007 Ω Q1 Si4410DY 9 8 7 6 RESET ON FILTER TIMER CTIMER 10nF GND CFILTER 100pF RAUTO (SEE NOTE) RPULL-UP 10k CAUTO 1 µF R3 10 Ω Z1* NOTE: Q1 MOUNTED TO 300mm2 COPPER AREA RAUTO = 1M YIELDS 2.5% DUTY CYCLE AND Q1 TCASE = 50°C RAUTO = 3.2M YIELDS 0.8% DUTY CYCLE AND Q1 TCASE = 37°C Z1 = 1SMA10A OR SMAJ10A * OPTIONAL 4211 F18 C1 0.1 µF R1 36k VOUT 5V 5A CLOAD R2 15k + LONG VCC 5V GND RESET LONG PCB EDGE CONNECTOR (MALE) BACKPLANE CONNECTOR (FEMALE) SHORT Figure 18. LTC4211MS Autoretry Application Figure 18. In this case, the autoretry circuitry will attempt to restart the LTC4211 with a 50% duty cycle, as shown in the timing diagram of Figure 19. To prevent overheating the external MOSFET and other components during the autoretry sequence, adding a capacitor (CAUTO) to the circuit introduces an RC time constant (tOFF) that adjusts the autoretry duty cycle. Equation 14 gives the autoretry duty cycle, modified by this external time constant: Autoretry Duty Cycle t tt TIMER OFF TIMER ≈ + 2 100 • •% (14) where tTIMER = LTC4211 system timing(see TIMER func- tion) and tOFF is a time needed to charge capacitor CAUTO from 0V to the ON pin threshold (1.316V). For the values shown, the external RC time constant is set at 1 second, the tTIMER delay equals 6.2ms and the autoretry duty cycle drops from 50% to 2.5%. + VCC SENSE LTC4211 8 2 34 76 CLOAD VOUT 12V 3A GND 4211 F17 5 1 R4 12.4k GATE GND TIMER PCB CONNECTION SENSE CTIMER 8.2nF FB ON SHORT LONG VCC 12V GND LONG Z1 = 1SMA12A OR SMAJ12A ** HIGHLY RECOMMENDED RESET R2 10k R1 61.9k RX 10 Ω RSENSE 0.012 Ω PCB EDGE CONNECTOR (MALE) M1 Si4410DY Z1** RG 100 Ω R3 93.1k R5 10k µP LOGIC RESET CX 100nF BACKPLANE CONNECTOR (FEMALE) |
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | 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 |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
