ncp59300 ON Semiconductor, ncp59300 Datasheet - Page 9

• Manufacturer Part Number: ncp59300
• Description: Ncp59300 3.0a, Very Low-dropout Vldo Fast Transient Response Regulator Series
• Manufacturer: ON Semiconductor

Output Capacitor and Stability
stable operation. The NCP59300 series is designed to
operate with ceramic output capacitors. The recommended
output capacitance value is 47 mF or greater. Such capacitors
help to improve transient response and noise reduction at
high frequency.
Input Capacitor
when the device is more than 4 inches away from the bulk
supply capacitance, or when the supply is a battery. Small,
surface−mount chip capacitors can be used for the
bypassing. The capacitor should be place within 1 inch of
the device for optimal performance. Larger values will help
to improve ripple rejection by bypassing the input of the
regulator, further improving the integrity of the output
voltage.
Minimum Load Current
loads. A 10 mA minimum load current is necessary for
proper operation.
Error Flag
circuit that monitors the output voltage and signals an error
condition when the voltage is 5% below the nominal output
voltage. The error flag is an open−collector output that can
sink up to 5 mA typically during a V
of the pullup load resistor occurs in the application. This is
guaranteed in the full range of FLG output voltage Max
ratings (see Max Ratings table).
Enable Input
input for on/off control of the device. It’s shutdown state
draws “zero” current from input voltage supply (only
microamperes of leakage). The enable input is TTL/CMOS
compatible for simple logic interface, but can be connected
up to V
Overcurrent and Reverse Output Current Protection
due to output current overload conditions. When NCP59300
output is overloaded, Output Current limiting is provided.
This limiting is linear; output current during overload
conditions is constant. The device is also capable to
withstand power−on or enable start−up with output shorted
to ground for the full Recommended Operating Conditions
range. These features are advantageous for powering
FPGAs and other ICs having current consumption higher
than nominal during their startup.
The NCP59300 series requires an output capacitor for
An input capacitor of 1.0 mF or greater is recommended
The NCP59300 regulator is specified between finite
Some NCP59300 series members feature an error flag
The FLG output is overload protected when a short circuit
Some NCP59300 series members also feature an enable
The NCP59300 regulator is fully protected from damage
IN
.
OUT
fault condition.
APPLICATIONS INFORMATION
http://onsemi.com
9
the die temperature exceeds the maximum safe operating
temperature.
in the application, the output structure of these regulators is
able to withstand output voltage (backup battery as
example) to be applied without reverse current flow. Of
course the additional current flowing through the internal
Feedback resistor divider at the NCP59300 Fix voltage
versions needs to be included in the backup battery
discharging calculations.
Adjustable Voltage Design
voltage is set by the ratio of two external resistors as shown
in Figure 23.
referenced to ground. The current in R2 is then equal to
1.24 V / R2, and the current in R1 is the current in R2 plus
the ADJ pin bias current. The ADJ pin bias current flows
from V
shown in Figure 23.
Thermal Considerations
the maximum rated junction temperature (125°C). The P
total power dissipated by the device has two components,
Input to output voltage differential multiplied by Output
current and Input voltage multiplied by GND pin current.
Characteristics table and in Typical Characteristics graphs.
The Junction temperature T
where T
Ambient Thermal Resistance of the NCP/NCV59300
device mounted on the specific PCB.
Thermal shutdown disables the NCP59300 device when
When (V
The NCP/NCV59302 Adjustable voltage Device Output
The device maintains the voltage at the ADJ pin at 1.24 V
The output voltage can be calculated using the formula
The power handling capability of the device is limited by
The GND pin current value can be found in Electrical
V
C
IN
IN
OUT
Figure 23. Adjustable Voltage Operation
A
P
V
is ambient temperature and R
+
D
OUT
OUT
through R1 into the ADJ pin.
+ V
+ 1.24 V @ 1 )
– V
IN
VIN
EN
T
NCP59302
IN
J
* V
+ T
) voltage difference is less than 6.5 V
GND
OUT
VOUT
A
ADJ
) P
J
is
@ I
D
OUT
R1
R2
@ R
) V
qJA
) I
R1
R2
qJA
ADJ
IN
is the Junction to
@ I
@ R1
+
C
47 mF,
Ceramic
GND
OUT
V
OUT
(eq. 1)
(eq. 2)
D