EVALPM6680A STMicroelectronics, EVALPM6680A Datasheet - Page 29

• Manufacturer Part Number: EVALPM6680A
• Description: EVAL BOARD FOR PM6680A
• Manufacturer: STMicroelectronics

Specifications of EVALPM6680A

• Mfg Application Notes: PM6680A, AN2565 Appl Note
• Main Purpose: DC/DC, Step Down with LDO
• Outputs And Type: 3, Non-Isolated
• Power - Output: 10.5W
• Voltage - Output: 1.8V, 3.3V, 5V
• Current - Output: 2.5A, 2.5A, 100mA
• Voltage - Input: 6 ~ 36V
• Regulator Topology: Buck
• Frequency - Switching: 200kHz, 300kHz
• Board Type: Fully Populated
• Utilized Ic / Part: PM6680A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6263

PM6680A
8
Monitoring and protections
Power good signals
The PM6680A provides two independent power good signals: one for each switching
section (PGOOD1/PGOOD2).
point or during the soft-start, standby and shutdown mode.
Thermal protection
The PM6680A has a thermal protection to preserve the device from overheating. The
thermal shutdown occurs when the die temperature goes above +150 °C. In this case all
internal circutry is turned off and the power sections are turned off after the discharge mode.
A power on reset or a toggle on the SHDN pin is necessary to restart the device.
Overvoltage protection
When the switching output voltage is about 115 % of its nominal value, a latched
overvoltage protection occurs. In this case, the synchronous rectifier immediately turns on
while the high-side MOSFET turns off. The output capacitor is rapidly discharged and the
load is preserved from being damaged. The overvoltge protection is also active during the
soft start. Once an overvoltage protection has been detected, a toggle on SHDN, EN1/EN2
pins or a power on reset is necessary to exit from the latched state.
Undervoltage protection
When the switching output voltage is below 70 % of its nominal value, a latched
undervoltage protection occurs. In this case the switching section is immediately disabled
and both switches are open. The controller enters in soft end mode and the output is
eventually kept to ground, turning low side MOSFET on. The undervoltage circuit protection
is enabled only at the end of the soft-start. Once an overvoltage protection has been
detected, a toggle on SHDN, EN1/EN2 pin or a power on reset is necessary to clear the
undervoltage fault and starts with a new soft-start phase.
Table 9.
PGOOD1/PGOOD2 signals are low if the output voltage is out of ± 10 % of the designed set
Undervoltage
Overvoltage
protection
protection
shutdown
Thermal
Mode
Protections and operatives modes
OUT1/OUT2 > 115% of the
OUT1/OUT2 < 70 % of the
nominal value
nominal value
T
Conditions
J
> +150
°
C
LGATE1/LGATE2 pin is forced high, LDO5 remains
active. Exit by a power on reset or toggling SHDN or
EN1/EN2
LGATE1/LGATE2 is forced high after the soft end
mode, LDO5 remains active. Exit by a power on reset
or toggling SHDN or EN1/EN2
All circuitry off. Exit by a POR on VIN or toggling
SHDN.
Description
Monitoring and protections
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