ncp1596 ON Semiconductor, ncp1596 Datasheet - Page 11

• Manufacturer Part Number: ncp1596
• Description: 1.5 A, 1.5 Mhz Current Mode Pwm Buck Down Converter
• Manufacturer: ON Semiconductor

Output Voltage Selection
resistor divider connect from V
resistor from FB to GND should be in 10 k to 20 k ranges.
The relationship between the output voltage and feedback
resistor is given by:
V
V
R1: Feedback resistor from V
R2: Feedback resistor from FB to GND.
Input Capacitor Selection
current with switching noise. Therefore, a bypass input
capacitor must choose for reduce the peak current drawn
from the power supply. For NCP1596, low ESR ceramic
capacitor of 10 mF should be used for most of cases. Also,
the input capacitor should be placed as close as possible to
the V
Inductor Selection
are DC resistance, inductor value and saturation current.
Inductor DC resistance will effect the convector overall
efficiency, low DC resistor value can provide a higher
efficiency. Thus, inductor value are depend on the inductor
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
ORDERING INFORMATION
Specifications Brochure, BRD8011/D.
NCP1596MNTWG
NCP1596AMNTWG
OUT
FB
The output voltage is programmed through an external
For internal compensation and noise immunity, the
In the PWM buck converter, the input current is pulsating
The inductor parameters are including three items, which
: Feedback Voltage
CCA
: Output voltage
V
OUT
pin for effective bypass the supply noise.
Device
+ V
FB
1 )
R1
R2
OUT
OUT
to FB.
to FB then to GND.
(Pb−Free)
(Pb−Free)
Package
DFN−6
DFN−6
APPLICATION INFORMATION
(eq. 1)
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11
ripple current, input voltage, output voltage, output current
and operation frequency, the inductor value is given by:
check out the inductor saturation current. The saturation
current of the inductor should be higher than the maximum
load plus the ripple current.
D
D
Output Capacitor Selection
voltage. For NCP1596, the output capacitor is required a
ceramic capacitors with low ESR value. Assume buck
converter duty cycle is 50%. The output ripple voltage in
PWM mode is given by:
be a good choice.
IL(MAX)
IOUT(MAX)
DIL : peak to peak inductor ripple current
L: inductor value
FSW: switching frequency
After selected a suitable value of the inductor, it should be
Output capacitor value is based on the target output ripple
In general, value of ceramic capacitor using 20 mF should
D
D
D
IL
IL(MAX)
VOUT
+
L
[ D
+ D
V
OUT
: Maximum inductor current
: Maximum output current
F
3000 / Tape & Reel
3000 / Tape & Reel
IL
SW
IOUT(MAX)
Shipping
4
1 *
)
FSW
†
D
V
2
V
IL
1
OUT
IN
C
OUT
) ESR
(eq. 2)
(eq. 3)
(eq. 4)