YKW-06 Datasheet, PDF (1/5 Pages) Weltrend Semiconductor – Step-down Switching Controller

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YKW-06
YKW-06
Preliminary release Rev. 0.30 20060118
Step-down Switching Controller
GENERAL DESCRIPTION
The YKW-06 is a step-down DC-DC converter. It could drivers an external power transistor using the
PWM control.
The IC incorporates the soft-start function with a proper capacitor connected between SS and
ground pins. The soft-start function could ensure the PWM output pulse width starts from 0% duty cycle.
The output voltage is controlled by the external sense resistor and FB pin. The output voltage are also
adjustable by the external variable resistor connected through SS and BRT pins. Through changing this
external resistor value, could tune the output current and voltage. It also has the over voltage detection
function with debounce-timer check to prevent from the over voltage damage.
FEATURES
• Operation voltage range : 2.4V ~ 6.0V
• Adjustable output voltage
• Built-in oscillator
• Soft start function
• Over voltage protection with the debounce-timer check.
• 8-pin DIP/MSOP/SOP packages
APPLICATIONS
• White LED lighting controllers
• Step-down DC-DC converters
• Portable equipment
PIN CONFIGURATION
OUT
1
SS
2
OVP
3
GND
4
8
VDD
7
COMP
6
BRT
5
FB
PIN DESCRIPTION
Pin No. Pin Name I/O
1
OUT
O
2
SS
B
3
OVP
I
4
GND
P
5
FB
I
6
BRT
I
7
COMP
O
8
VDD
P
Description
PWM output (High : PWM on period)
Soft-start timing Setting with external capacitor
Over voltage protection and Disable function
Ground
Output voltage feedback sense, error amplifier(-) input
Output current setting , error amplifier(+) input
Output voltage, error amplifier(o) output
Power supply
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