Electronic Components Datasheet Search |
|
SIC734CD9 Datasheet(PDF) 6 Page - Vishay Siliconix |
|
SIC734CD9 Datasheet(HTML) 6 Page - Vishay Siliconix |
6 / 10 page www.vishay.com 6 Document Number: 73672 S-62656–Rev. C, 25-Dec-06 Vishay Siliconix SiC734CD9 DEVICE OPERATION Pulse Width Modulator (PWM) This is a CMOS compatible logic input that receives the drive signals from the controller circuit. The PWM signal drives the buck switch. Break-Before-Make (BBM) The SiC730CD9 has an intrenal break-before-make function to ensure that both high-side and low-side MOSFETs are not turned on the same time. The low-side MOSFET will not turn on until the high-side gate drive voltage is less than VBBM, thus ensuring that the high-side MOSFET is turned off. This parameter is not user adjustable. SHDN CMOS logic signal. In the low state, the SHDN disables both high-side and low-side MOSFET’s. Capacitor to Boot Input (CBOOT) Connected to VDD by an internal diode via the CBOOT pin, the boot capacitor is used to sustain rail for the high-side MOS- FET gate drive circuit. Under Voltage Lockout (UVLO) During the start up cycle, the UVLO disables the gate drive holding high-side and low-side MOSFET’s low until the input voltage rail has reached a point at which the logic circuitry can be safely activated. The UVLO is not user adjustable. SYNC Pin for Pre-Bias Start-Up The low side MOSFET can be individually enable or dis- abled by using the SYNC pin. In the low state (SYNC = low), the low-side MOSFET is turned off. In the high state, the low-side MOSFET is enabled and follows the PWM input signal (see timing diagram, Figure 2). SYNC is a CMOS compatible logic input and is used for a pre–biased output voltage. Voltage Input (VIN) This is the power input to the drain of the high-side Power MOSFET. This pin is connected to the high power intermedi- ate BUS rail. Switch Node (SW) The Switch node is the circuit PWM regulated output. This is the output applied to the filter circuit to deliver the regulated high output for the buck converter. Power Ground (PGND) This is the output connection from the source of the low-side MOSFET. This output is the ground return loop for the power rail. It should be externally connected to CGND. Control Ground (CGND) This is the control voltage return path for the driver and logic input circuitry to the SiC730CD9. This should externally con- nected to PGND. APPLICATION CIRCUIT The SiC734CD9 has a built-in delay time that is optimized for the MOSFET pair. When the PWM signal goes low, the high- side driver will turn off, after circuit delay (tdoff), and the out- put will start to ramp down, (tf). After a further delay, the low- side driver turns on. When the PWM goes high, the low-side driver turns off, (tdon). As the body diode starts to conduct, the high-side MOSFET turns on after a short dalay. The delay is minimized to limit body diode conduction. The output then ramps up, (tr). CGND 5 V 3.3 V to 16 V MOSFET Drive Circuitry with Break-Before- Make CBOOT VIN SW CBOOT L + PGND CGND SHDN VDD Q1 Q2 DC-DC Controller VOUT PWM SYNC Power Up Sequence: The presence of VDD prior to applying the VIN and PWM is recommended to ensure a safe turn on Power Down Sequence: The sequence should be reverse of the on sequence, turn off the VIN before turning off the VDD. PGND HS LS Figure 7 The SiC714CD10 has a built-in delay time that is optimized for the MOSFET pair. When the PWM signal goes low, the high-side driver will turn off, after circuit delay (tdoff), and the output will start to ramp down,(tf). After a further delay, the low-side driver turns on. When the PWM goes high, the low-side driver turns off,(tdon). As the body diode starts to conduct, the high-side MOSFET turns on after a short delay . The delay is minimized to limit body diode conduction. The output then ramps up,(tr). |
Similar Part No. - SIC734CD9 |
|
Similar Description - SIC734CD9 |
|
|
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 |