STEVAL-ISA027V1 STMicroelectronics, STEVAL-ISA027V1 Datasheet - Page 19

• Manufacturer Part Number: STEVAL-ISA027V1
• Description: BOARD EVAL 1PH STPDN CONV L6726A
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of STEVAL-ISA027V1

• Design Resources: STEVAL-ISA027V1 Gerber Files STEVAL-ISA027V1 Schematic STEVAL-ISA027V1 Bill of Material
• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 1.25V
• Current - Output: 20A
• Voltage - Input: 5 ~ 12V
• Regulator Topology: Buck
• Frequency - Switching: 270kHz
• Board Type: Fully Populated
• Utilized Ic / Part: L6726A
• Input Voltage: 5 V to 12 V
• Output Voltage: 1.25 V
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: L6726A
• Other names: 497-6259

L6726A
Application details
Connect output bulk capacitors (C
) as near as possible to the load, minimizing parasitic
OUT
inductance and resistance associated to the copper trace, also adding extra decoupling
capacitors along the way to the load when this results in being far from the bulk capacitors
bank.
Gate traces and phase trace must be sized according to the driver RMS current delivered to
the power MOSFET. The device robustness allows managing applications with the power
section far from the controller without losing performances. Anyway, when possible, it is
recommended to minimize the distance between controller and power section. See
Figure 11
for drivers current paths.
Small signal components and connections to critical nodes of the application, as well as
bypass capacitors for the device supply, are also important. Locate bypass capacitor (VCC
and Bootstrap capacitor) and loop compensation components as close to the device as
practical. For over current programmability, place R
close to the device and avoid
OCSET
leakage current paths on LGATE / OC pin, since the internal current source is only 10 μA
Systems that do not use Schottky diode in parallel to the Low-Side MOSFET might show big
negative spikes on the PHASE pin. This spike must be limited within the absolute maximum
ratings (for example, adding a gate resistor in series to HS MOSFET gate, or a phase
resistor in series to PHASE pin), as well as the positive spike, but has an additional
consequence: it causes the bootstrap capacitor to be over-charged. This extra-charge can
cause, in the worst case condition of maximum input voltage and during particular
transients, that boot-to-phase voltage overcomes the absolute maximum ratings also
causing device failures. It is then suggested in this case to limit this extra-charge by adding a
small resistor in series to the bootstrap diode (R
in
Figure
1).
D
Figure 11. Drivers turn-on and turn-off paths
LS DRIVER
LS MOSFET
HS DRIVER
HS MOSFET
VCC
BOOT
C
C
GD
GD
R
R
R
R
GATE
INT
GATE
INT
LGATE
UGATE
C
C
C
C
GS
DS
GS
DS
R
PHASE
GND
PHASE
Doc ID 12754 Rev 4
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