NCV3020BDR2G ON Semiconductor, NCV3020BDR2G Datasheet - Page 14

• Manufacturer Part Number: NCV3020BDR2G
• Description: IC PWM CTLR SYNC 8SOIC
• Manufacturer: ON Semiconductor
• Series: -r

Specifications of NCV3020BDR2G

• Pwm Type: Voltage Mode
• Number Of Outputs: 1
• Frequency - Max: 670kHz
• Duty Cycle: 80%
• Voltage - Supply: 4.7 V ~ 28 V
• Buck: Yes
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

the low side MOSFET is off for the majority of the switching
period. Reduced sampling time causes errors in the
regulated voltage on the boost pin. High duty cycle / input
voltage induced sampling errors can result in increased
boost ripple voltage or higher than desired DC boost voltage.
Figure 29 outlines all operating regions.
Region 1 (Green) where a 0.1 mF, 25 V ceramic capacitor
can be placed on the boost pin without causing damage to the
device or MOSFETS. Larger boost ripple voltage occurring
over several switching cycles is shown in Region 2 (Yellow).
Reduced sampling time occurs at high duty cycles where
The recommended operating conditions are shown in
Figure 29. Safe Operating Area for Boost Voltage with a 0.1 mF Capacitor
28
26
24
22
20
18
16
14
12
10
8
6
4
2
Normal Operation
5
10
15
20
25
Boost Voltage Levels
30
http://onsemi.com
35
Increased Boost Ripple
(Still in Specification)
Region 1
40
11.5V
22V
Duty Cycle
14
45
The boost ripple frequency is dependent on the output
capacitance selected. The ripple voltage will not damage the
device or $12 V gate rated MOSFETs.
damage the device or $12 V gate rated MOSFETs can be
seen in Region 3 (Orange). Placing a boost capacitor that is
no greater than 10X the input capacitance of the high side
MOSFET on the boost pin limits the maximum boost
voltage < 12 V. The typical drive waveforms for Regions 1,
2 and 3 (green, yellow, and orange) regions of Figure 29 are
shown in Figure 30.
50
Conditions where maximum boost ripple voltage could
55
60
65
70
Increased Boost Ripple
Capacitor Optimization
71%
Region 2
Region 3
75
Required
80
85
Cycle
Duty
Max
Cycle
mum
Maxi
Duty
90