NCP3066PG ON Semiconductor, NCP3066PG Datasheet - Page 7

• Manufacturer Part Number: NCP3066PG
• Description: IC LED DRIVER HIGH BRIGHT 8-DIP
• Manufacturer: ON Semiconductor
• Type: HBLED Driverr

Specifications of NCP3066PG

• Constant Current: Yes
• Topology: PWM, Step-Down (Buck), Step-Up (Boost)
• Number Of Outputs: 1
• Internal Driver: Yes
• Type - Primary: Automotive
• Type - Secondary: High Brightness LED (HBLED)
• Frequency: 110kHz ~ 190kHz
• Voltage - Supply: 3 V ~ 40 V
• Mounting Type: Through Hole
• Package / Case: 8-DIP (0.300", 7.62mm)
• Operating Temperature: 0°C ~ 85°C
• Current - Output / Channel: 1.5A
• Internal Switch(s): Yes
• Output Voltage: 1 V
• Output Current: 1 uA
• Input Voltage: 0 V to 42 V
• Switching Frequency: 100 KHz to 250 KHz
• Mounting Style: Through Hole
• Duty Cycle (max): 100 %
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Efficiency: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: NCP3066PG; NCP3066PGOS

optimized for LED Driver applications. Its flexible
architecture enables the system designer to directly
implement step−up, step−down, and voltage−inverting
converters with a minimum number of external components
for driving LEDs. A representative block diagram is shown
in Figure 3.
Operating Description
output voltage ripple gated regulator. In general, this mode
of operation is somewhat analogous to a capacitor charge
pump and does not require dominant pole loop
compensation for converter stability. The typical operating
waveforms are shown in Figure 12. The output voltage
waveform is shown for a step−down converter with the
ripple and phasing exaggerated for clarity. During initial
converter startup, the feedback comparator senses that the
output voltage level is below nominal. This causes the
output switch to turn on and off at a frequency and duty cycle
controlled by the oscillator, thus pumping up the output filter
capacitor. When the output voltage level reaches nominal
The NCP3066 is a monolithic power switching regulator
The NCP3066 operates as a fixed oscillator frequency
Figure 12. Typical Operating Waveforms
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INTRODUCTION
7
comparator value, the output switch cycle is inhibited. When
the load current causes the output voltage to fall below the
nominal value feedback comparator enables switching
immediately. Under these conditions, the output switch
conduction can be enabled for a partial oscillator cycle, a
partial cycle plus a complete cycle, multiple cycles, or a
partial cycle plus multiple cycles.
Oscillator
are programmed by the value of the timing capacitor C
capacitor C
internal current source and sink, generating a positive going
sawtooth waveform at Pin 3. This ratio sets the maximum
t
85.7% (typical). The oscillator peak and valley voltage
difference is 500 mV typically. To calculate the C
value for required oscillator frequency, use the equations
found in Figure 15. An online NCP3066 design tool can be
found at www.onsemi.com, which aids in selecting
component values.
ON
The oscillator frequency and off−time of the output switch
/(t
ON
+ t
T
OFF
is charged and discharged by a 1 to 6 ratio
) of the switching converter as 6/(6+1) or
T
capacitor
T
. The