L6714 STMicroelectronics, L6714 Datasheet - Page 56

• Manufacturer Part Number: L6714
• Description: IC CTRLR 4PH W/DRIVERS 64-TQFP
• Manufacturer: STMicroelectronics

Specifications of L6714

• Applications: Controller, Intel VR10, VR11, AMD CPU
• Voltage - Input: 12V
• Number Of Outputs: 4
• Voltage - Output: 0.3 ~ 1.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 64-TQFP Exposed Pad, 64-eTQFP, 64-HTQFP, 64-VQFP
• Mounting Style: SMD/SMT
• Case: QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Driver section
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Driver section
The integrated high-current drivers allow using different types of power MOS (also multiple
MOS to reduce the equivalent R
The drivers for the high-side MOSFETs use BOOTx pins for supply and PHASEx pins for
return. The drivers for the low-side MOSFETs use VCCDRx pin for supply and PGNDx pin
for return. A minimum voltage at VCCDRx pin is required to start operations of the device.
VCCDRx pins must be connected together.
The controller embodies a sophisticated anti-shoot-through system to minimize low side
body diode conduction time maintaining good efficiency saving the use of Schottky diodes:
when the high-side MOSFET turns off, the voltage on its source begins to fall; when the
voltage reaches 2V, the low-side MOSFET gate drive is suddenly applied. When the low-
side MOSFET turns off, the voltage at LGATEx pin is sensed. When it drops below 1V, the
high-side MOSFET gate drive is suddenly applied.
If the current flowing in the inductor is negative, the source of high-side MOSFET will never
drop. To allow the turning on of the low-side MOSFET even in this case, a watchdog
controller is enabled: if the source of the high-side MOSFET doesn't drop, the low side
MOSFET is switched on so allowing the negative current of the inductor to recirculate. This
mechanism allows the system to regulate even if the current is negative.
The BOOTx and VCCDRx pins are separated from IC's power supply (VCC pin) as well as
signal ground (SGND pin) and power ground (PGNDx pin) in order to maximize the
switching noise immunity. The separated supply for the different drivers gives high flexibility
in MOSFET choice, allowing the use of logic-level MOSFET. Several combination of supply
can be chosen to optimize performance and efficiency of the application.
Power conversion input is also flexible; 5V, 12V bus or any bus that allows the conversion
(See maximum duty cycle limitations) can be chosen freely.
dsON
), maintaining fast switching transition.
L6714