Datasheet LT1615, LT1615-1 (Analog Devices) - 3

LT1615/LT1615-1
W U TYPICAL PERFOR A CE CHARACTERISTICS Switch Saturation Voltage Feedback Pin Voltage and (VCESAT) Bias Current Quiescent Current
0.60 1.25 50 25 0.55 VFB = 1.23V NOT SWITCHING 0.50 1.24 40 23 BIAS CURRENT (nA) µA) 0.45 VOLTAGE ISWITCH = 500mA 0.40 1.23 30 21 0.35 VIN = 12V 0.30 1.22 CURRENT 20 19 ISWITCH = 300mA SWITCH VOLTAGE (V) 0.25 VIN = 1.2V FEEDBACK VOLTAGE (V) QUIESCENT CURRENT ( 0.20 1.21 10 17 0.15 0.10 1.20 0 15 –50 –25 0 25 50 75 100 –50 –25 0 25 50 75 100 –50 –25 0 25 50 75 100 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 1615/-1 G01 1615/-1 G02 1615/-1 G03
Switch Off Time Switch Current Limit Shutdown Pin Current
550 400 25 VIN = 12V 350 500 VIN = 1.2V µA) 20 300 LT1615 450 250 15 V 400 IN = 1.2V 200 25°C V 10 IN = 12V 150 350 100°C LT1615-1 VIN = 12V SWITCH OFF TIME (ns) PEAK CURRENT (mA) 100 V 5 300 IN = 1.2V SHUTDOWN PIN CURRENT ( 50 250 0 0 –50 –25 0 25 50 75 100 –50 –25 0 25 50 75 100 0 5 10 15 TEMPERATURE (°C) TEMPERATURE (°C) SHUTDOWN PIN VOLTAGE (V) 1615/-1 G04 1615/-1 G05 1615/-1 G03
U U U PI FU CTIO S SW (Pin 1):
Switch Pin. This is the collector of the internal
SHDN (Pin 4):
Shutdown Pin. Tie this pin to 0.9V or higher NPN power switch. Minimize the metal trace area con- to enable the device. Tie below 0.25V to turn off the device. nected to this pin to minimize EMI.
VIN (Pin 5):
Input Supply Pin. Bypass this pin with a
GND (Pin 2):
Ground. Tie this pin directly to the local capacitor as close to the device as possible. ground plane.
FB (Pin 3):
Feedback Pin. Set the output voltage by selecting values for R1 and R2 (see Figure 1):  V  R = R OUT 1 2 − 1  1 23  . sn16151 16151fas 3