EN5339QI-E Enpirion, EN5339QI-E Datasheet - Page 12

• Manufacturer Part Number: EN5339QI-E
• Description: Power Management IC Development Tools EN5339QI EVAL BOARD
• Manufacturer: Enpirion
• Type: DC/DC Converters, Regulators & Controllersr

Specifications of EN5339QI-E

• Product Category: Power Management IC Development Tools
• Product: Evaluation Boards
• Tool Is For Evaluation Of: EN5339QI
• Input Voltage: 2.4 V to 5.5 V
• Output Voltage: 0.6 V
• Output Current: 3 A

the electrical characteristics table.
Excess bulk capacitance on the output of the
device can cause an over-current condition at
startup. Since the slew rate varies with the output
voltage setting, the maximum capacitance is a
function of the VOUT setting.
The maximum capacitance on the output power
rail, including the output filter capacitors and all
decoupling and bulk capacitors on the supply rail is
given by:
C
NOTE: The above number and formula assume a
no load condition at startup.
Over Current/Short Circuit Protection
When an over current condition occurs, V
pulled low. This condition is maintained for a period
of 1.2 ms and then a normal soft start cycle is
initiated. If the over current condition still persists,
this cycle will repeat.
Under Voltage Lockout
An under voltage lockout circuit will hold off
switching during initial power up until the input
voltage reaches sufficient level to ensure proper
operation. If the voltage drops below the UVLO
threshold the lockout circuitry will again disable
switching. Hysteresis is included to prevent
chattering between UVLO high and low states.
Enable
The ENABLE pin provides means to shut down the
converter or initiate normal operation. A logic high
will enable the converter to go through the soft start
cycle and regulate the output voltage to the desired
value. A logic low will allow the device to discharge
the output and go into shutdown mode for minimal
power
discharged, an auxiliary NFET turns on and limits
the discharge current to 300 mA or below. The
ENABLE pin must not be left floating.
Thermal Shutdown
When excessive power is dissipated in the device,
its junction temperature rises. Once the junction
temperature
temperature 155° C, the thermal shutdown circuit
turns off the converter, allowing the device to cool.
When the junction temperature drops 15° C, the
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OUT_TOTAL_MAX
consumption.
[F] = 3.6x10
exceeds
When
the
-3
/V
OUT
thermal
the
output
shutdown
OUT
is
is
Enpirion Confidential
device will be re-enabled and go through a normal
startup process.
Power OK
The EN5339 provides an open drain output to
indicate if the output voltage stays within 92% to
111% of the set value. Within this range, the POK
output is allowed to be pulled high. Outside this
range,
transitions such as power up, power down, and
dynamic voltage scaling, the POK output will not
change state until the transition is complete for
enhanced noise immunity.
The POK has 5 mA sink capability for events where
it needs to feed a digital controller with standard
CMOS inputs. When POK is pulled high, the pin
leakage current is as low as 500 nA maximum over
temperature. This allows a large pull up resistor
such as 100 k
consumption in shutdown mode.
The POK output can also be conveniently used as
an ENABLE input of the next stage for power
sequencing of multiple converters.
POK
remains
to be used for minimal current
www.enpirion.com, Page 12
low.
However,
EN5339QI
during