EUP2571
Typical Application Circuit (continued)
Figure 2. 5V to 9V/300mA Step-Up Application
Pin Configurations
Package Type
Pin Configurations
Package Type
Pin Configurations
SOT23-5
SOT23-6
Pin Description
PIN
LX
SOT23-5 SOT23-6
DESCRIPTION
Switch Pin. Connect inductor/diode here. Minimize trace area at this pin to
reduce EMI.
1
2
1
2
GND
Common Ground
Feedback Pin. Reference voltage is 0.25V. Connect cathode of lowest LED
and resistor here. Calculate resistor value according to the formula:
RFB=0.25/ILED
FB
3
3
Chip Enable Pin. Connect to 1.4V or higher to enable device, 0.4V or less to
disable device.
EN
IN
4
5
4
6
Input Supply Voltage
Overvoltage Sense. When VOUT is greater than 27V, the internal N-channel
MOSFET turns off until VOUT drops below 25V, then the IC reenters start.
Connect a 1uF capacitor from OUT to GND.
OUT
-
5
DS2571 Ver1.1 May. 2007
2
EUTECH [ EUTECH MICROELECTRONICS INC ]
