NCP3126ADR2G ON Semiconductor, NCP3126ADR2G Datasheet - Page 16

• Manufacturer Part Number: NCP3126ADR2G
• Description: DC/DC Switching Converters 3A PWM Switching Buck Regulator
• Manufacturer: ON Semiconductor

Specifications of NCP3126ADR2G

• Mounting Style: SMD/SMT
• Duty Cycle (max): 80 %
• Efficiency: 93 %
• Input / Supply Voltage (max): 13.2 V
• Input / Supply Voltage (min): 4.5 V
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 125 C
• Output Current: 3 A
• Output Voltage: Adjustable
• Supply Current: 10 mA
• Switching Frequency: 350 KHz
• Package / Case: SOIC-8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

C
f
R
R
R
The cross over of the overall feedback occurs at F
C
F
F
R
R
R
V
V
used to calculate the transconductance output compensation
network as follows:
C
F
gm
R
R
cross
C
239 pF +
F
LC
PO
PO
F
1
2
F
12.69 kHz +
F
1
2
F
IN
ramp
C
1
2
The cross over combined compensation network can be
PO
F
+
76 nF +
+
C
2p
2p
C
+
2p
2
F
12.69 kHz
R
= Feed through capacitor
= Crossover frequency
= Top resistor divider
= Bottom resistor divider
= Feed through resistor
= Feed through capacitor
= Frequency of the output inductor and capacitor
= Pole frequency
= Top of resistor divider
= Bottom of resistor divider
= Feed through resistor
= Input voltage
= Peak−to−peak voltage of the ramp
= Compensation capacitor
= Pole frequency
= Transconductance of amplifier
= Top of resistor divider
= Bottom of resistor divider
1
PO
2p
1
C
) R
31.6 kW
2
1
F
2
R
F
R
2
239 pF
) R
R
1
) R
2
R
R
10 kW ) 31.6 kW
2
1
1
20 kW ) 10 kW
F
2
) R
R
R
31.6 kW ) 20 kW
gm ³
10 kW
1
F
) R
2
R
) R
2
) R
F
2
31.6 kW ) 10 kW
1
R
1
R
F
4 ms
20 kW ) 10 kW
31.6 kW ) 20 kW
PO
f
cross
http://onsemi.com
10 kW ) 31.6 kW
:
R
F
) R
(eq. 42)
1
16
FLC
31.6 kW
V
ramp
20 kW
V
IN
³
30 kHz
20 kW ) 31.6 kW
(eq. 41)
(eq. 40)
2.82 kHz
1.1 V
12 V