APL5930 Anpec Electronics Corporation, APL5930 Datasheet - Page 10
APL5930
Manufacturer Part Number
APL5930
Description
3a, Ultra Low Dropout 0.23v Typical Linear Regulator
Manufacturer
Anpec Electronics Corporation
Datasheet
1.APL5930.pdf
(16 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
APL5930QBI-TRG
Manufacturer:
ANPEC/茂达电子
Quantity:
20 000
APL5930
Function Description
Power-On-Reset
A Power-On-Reset (POR) circuit monitors both of supply
voltages on VCNTL and VIN pins to prevent wrong logic
controls. The POR function initiates a soft-start process
after both of the supply voltages exceed their rising POR
voltage thresholds during powering on. The POR func-
tion also pulls low the POK voltage regardless the output
status when one of the supply voltages falls below its
falling POR voltage threshold.
Internal Soft-Start
An internal soft-start function controls rise rate of the out-
put voltage to limit the current surge during start-up. The
typical soft-start interval is about 0.6 ms.
Output Voltage Regulation
An error amplifier works with a temperature-com-
pensated 0.8V reference and an output NMOS regulates
output to the preset voltage. The error amplifier is de-
signed with high bandwidth and DC gain provides very
fast transient response and less load regulation. It com-
pares the reference with the feedback voltage and ampli-
fies the difference to drive the output NMOS which pro-
vides load current from VIN to VOUT.
Current-Limit Protection
The APL5930 monitors the current flowing through the
output NMOS and limits the maximum current to prevent
load and APL5930 from damages during current over-
load conditions.
Short Current-Limit Protection
The short current-limit function reduces the current-limit
level down to 1.1A (typical) when the voltage on FB pin
falls below 0.2V (typical) during current overload or short-
circuit conditions.
The short current-limit function is disabled for success-
ful start-up during soft-start interval.
Copyright
Rev. A.1 - Jun., 2008
ANPEC Electronics Corp.
10
Thermal Shutdown
A thermal shutdown circuit limits the junction tempera-
ture of APL5930. When the junction temperature exceeds
+170
lowing the device to cool down. The regulator regulates
the output again through initiation of a new soft-start pro-
cess after the junction temperature cools by 50
ing in a pulsed output during continuous thermal over-
load conditions. The thermal shutdown is designed with
a 50
ture during continuous thermal overload conditions, ex-
tending lifetime of the device.
For normal operation, the device power dissipation should
be externally limited so that junction temperatures will
not exceed +125
Enable Control
The APL5930 has a dedicated enable pin (EN). A logic
low signal applied to this pin shuts down the output. Fol-
lowing a shutdown, a logic high signal re-enables the
output through initiation of a new soft-start cycle. When
left open, this pin is pulled up by an internal current source
(5 A typical) to enable normal operation. It’ s not neces-
sary to use an external transistor to save cost.
Power-OK and Delay
The APL5930 indicates the status of the output voltage by
monitoring the feedback voltage (V
V
old (V
the end of the delay time, the IC turns off the internal
NMOS of the POK to indicate that the output is ok. As the
V
threshold, the IC turns on the NMOS of the POK (after a
debounce time of 10 s typical).
FB
FB
rises and reaches the rising Power-OK voltage thresh-
falls and reaches the falling Power-OK voltage
o
o
C hysteresis to lower the average junction tempera-
C, a thermal sensor turns off the output NMOS, al-
THPOK
), an internal delay function starts to work. At
o
C.
FB
www.anpec.com.tw
) on FB pin. As the
o
C, result-