ADP2380-EVALZ Analog Devices, ADP2380-EVALZ Datasheet - Page 14

• Manufacturer Part Number: ADP2380-EVALZ
• Description: Power Management IC Development Tools 20V 4A Evaluation Board
• Manufacturer: Analog Devices
• Type: DC/DC Converters, Regulators & Controllersr
• Series: ADP2380r

Specifications of ADP2380-EVALZ

• Rohs: yes
• Tool Is For Evaluation Of: ADP2380
• Input Voltage: 4.5 V to 20 V
• Factory Pack Quantity: 1

ADP2380
If the output voltage is charged prior to turn-on, the
prevents the low-side MOSFET from turning on, which discharges
the output voltage until the soft start voltage exceeds the voltage
on the FB pin.
When the regulator is disabled or a current fault happens, the
soft start capacitor is discharged, and the internal digital soft
start is reset to 0 V.
POWER GOOD
The power-good (PGOOD) pin is an active high, open-drain
output that requires a pull-up resistor. A logic high indicates
that the voltage at the FB pin (and, therefore, the output
voltage) is above 95% of the reference voltage and there is a
1024 cycle waiting period before PGOOD is pulled high. A logic
low indicates that the voltage at the FB pin is below 90% of the
reference voltage and there is a 16-cycle waiting period before
PGOOD is pulled low.
PEAK CURRENT-LIMIT AND SHORT-CIRCUIT
PROTECTION
The
prevent current runaway. During soft start, the
frequency foldback to prevent output current runaway. The
switching frequency is reduced according to the voltage on the
FB pin, which allows more time for the inductor to discharge.
The correlation between the switching frequency and FB pin
voltage is shown in Table 5.
Table 5. Switching Frequency and FB Pin Voltage
FB Pin Voltage
V
0.4 V > V
V
For heavy load protection, the
overcurrent protection. When the inductor peak current reaches
the current-limit value, the high-side MOSFET turns off and
the low-side driver turns on until the next cycle, while the
overcurrent counter increments. If the overcurrent counter
reaches 10, or the FB pin voltage falls to ≤0.4 V after the soft
start, the regulator enters hiccup mode. The high-side MOSFET
and low-side MOSFET are both turned off. The regulator remains
in this mode for 4096 clock cycles and then attempts to restart.
FB
FB
≥ 0.4 V
< 0.2 V
ADP2380
FB
≥ 0.2 V
has a peak current-limit protection circuit to
ADP2380
Switching Frequency
f
f
f
SW
SW
SW
/2
/4
uses hiccup mode for
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ADP2380
uses
Rev. 0 | Page 14 of 28
If the current-limit fault is cleared, the regulator resumes
normal operation. Otherwise, it reenters hiccup mode.
The
low-side MOSFET from sinking a large amount of current from
the load. When the voltage across the low-side MOSFET exceeds
the sink current-limit threshold, which is typically 20 mV, the
low-side MOSFET turns off immediately for the rest of this cycle.
Both high-side and low-side MOSFETs turn off until the next
clock cycle.
In some cases, the input voltage (PVIN) ramp rate is too slow or
the output capacitor is too large to support the setting regulation
voltage during the soft start, causing the regulator to enter hiccup
mode. To avoid such cases, use a resistor divider at the UVLO
pin to program the UVLO input voltage, or use a longer soft
start time.
OVERVOLTAGE PROTECTION (OVP)
The
protect the system against an output that shorts to a higher
voltage supply or the occurrence of a strong load transient.
If the feedback voltage increases to 0.7 V, the internal high-side
MOSFET and low-side driver are turned off until the voltage at FB
decreases to 0.63 V. At that time, the
operation.
UNDERVOLTAGE LOCKOUT (UVLO)
The UVLO pin enable threshold is 1.2 V with 100 mV hysteresis.
The
two resistors from PVIN to GND, with 320 kΩ for the high-side
resistor and 125 kΩ for the low-side resistor. An external resistor
divider from PVIN to GND can be used to override the internal
resistor divider.
THERMAL SHUTDOWN
In the event that the
150°C, the thermal shutdown circuit turns off the regulator.
Extreme junction temperatures can be the result of high current
operation, poor circuit board design, and/or high ambient
temperature. A 25°C hysteresis is included so that, when thermal
shutdown occurs, the
the on-chip temperature drops below 125°C. Upon recovery, soft
start is initiated prior to normal operation.
ADP2380
ADP2380
ADP2380
also provides a sink current limit to prevent the
provides an overvoltage protection feature to
has an internal voltage divider that consists of
ADP2380
ADP2380
junction temperatures rise above
does not return to operation until
ADP2380
resumes normal
Data Sheet