EVALA5970D STMicroelectronics, EVALA5970D Datasheet - Page 11

• Manufacturer Part Number: EVALA5970D
• Description: Power Management Modules & Development Tools EVAL BOARD A5970D Auto Grade
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of EVALA5970D

• Input Voltage: 4.4 V to 36 V
• Output Voltage: 1.235 V to 35 V
• Board Size: 23 mm x 20 mm
• Product: Power Management Modules
• Supply Current: 1 A
• Dimensions: 23 mm x 20 mm
• For Use With/related Products: AN1330
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AN1330
3
3.1
3.2
3.3
Additional features and protection
Feedback disconnection
If the feedback is disconnected, the duty cycle increases towards the maximum allowed
value, bringing the output voltage close to the input supply. This condition could destroy the
load.
To avoid this hazardous condition, the device is turned OFF if the feedback pin is left
floating.
Output overvoltage protection
Overvoltage protection, or OVP, is achieved by using an internal comparator connected to
the feedback, which turns OFF the power stage when the OVP threshold is reached. This
threshold is typically 30% higher than the feedback voltage.
When a voltage divider is required to adjust the output voltage
intervention will be set at:
Equation 1
Where R
R
Zero load
Due to the fact that the internal power is a PDMOS, no bootstrap capacitor is required and
so the device works properly even with no load at the output. In this condition it works in
burst mode, with random burst repetition rate.
2
is between the feedback pin and ground.
1
is the resistor connected between the output voltage and the feedback pin, and
V OVP
=
1.3
•
R
--------------------- -
1
R 2
+
R
2
Additional features and protection
•
V FB
(Figure
14), the OVP
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