p1686 Unisonic Technologies, p1686 Datasheet - Page 2

• Manufacturer Part Number: p1686
• Description: 600khz, 3a Step-down Current Mdoe Switching Regulator
• Manufacturer: Unisonic Technologies

P1686
PIN NO.
1
2
3
4
5
6
7
8
PIN DESCRIPTION
PIN CONFIGURATION
PIN NAME
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
COMP
SYNC
GND
BST
SW
EN
FB
IN
GND
BST
SW
IN
Providing power to the internal NPN switch. To turn on for this switch the lowest voltage is
2.7V.
This PIN delivers all control and power circuitry’s power, and sees high di/dt during
switching. A decoupling capacitor is better to be attached to this pin very closely.
This PIN is the emitter of the internal switch and should be connected with the external
freewheeling diode very closely.
Almost all voltages are measured with respect to this pin. The decoupling capacitor and the
freewheeling diode is better to be connected to this PIN as short as possible.
Input of feedback for adjustable output controllers.
Output of the internal error amplifier and also input of the peak current comparator. To
achieve the specified performance a compensation network is connected to this pin.
Chip enable input. EN is high: the regulator switched on; EN is low: off. EN is low: the
regulator is in standby mode, and the input supply current is reduced to a few
microamperes.
Synchronous control pin used to synchronize the internal oscillator to an external pulse
control signal. But it should be connected to GND when not used.
1
2
3
4
SOP-8
8
7
6
5
SYNC
FB
EN
COMP
GND
BST
PIN FUNCTION
SW
IN
1
2
3
4
LINEAR INTEGRATED CIRCUIT
HSOP-8
8
7
6
5
SYNC
FB
EN
COMP
QW-R103-039.C
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