LT3463/LT3463A
TYPICAL PERFOR A CE CHARACTERISTICS
V
CESAT
and V
DIODE
Voltage
900
800
V
CESAT
AND V
DIODE
VOLTAGE (V)
700
600
500
400
300
200
100
I
SWITCH
= 150mA
0
25
50
75
100
125
FOR BOTH SWITCHERS
I
DIODE
= 150mA
V
REF
AND V
FB1
VOLTAGE (V)
1.25
V
FB1
V
REF
V
FB2
VOLTAGE (mV)
0
–50 –25
TEMPERATURE (°C)
3463 G01
Switch Off Time
400
350
450
400
SWITCH CURRENT LIMIT (mA)
SWITCH OFF TIME (ns)
300
250
200
150
100
50
0
–50 –25
0
25
50
75
100
125
300
250
200
150
100
50
0
–50 –25
0
25
50
75
100
125
LT3463 SW1, SW2
LT3463A SW1
QUIESCENT CURRENT (µA)
TEMPERATURE (°C)
3463 G04
PI FU CTIO S
V
OUT1
(Pin 1):
Output Voltage Switcher 1. This is the
cathode of an internal Schottky diode whose anode is
connected to the SW1 pin.
SW1 (Pin 2):
Switch Pin for Switcher 1. This is the
collector of the internal NPN switch. Minimize the metal
trace area connected to this pin to minimize EMI.
V
IN
(Pin 3):
Input Supply Pin. Bypass this pin with a
capacitor as close to the device as possible.
SW2 (Pin 4):
Switch Pin for Switcher 2. This is the
collector of the internal NPN switch. Minimize the metal
trace area connected to this pin to minimize EMI.
D2 (Pin 5):
Diode for Switcher 2. This is the anode of an
internal Schottky diode whose cathode connected to the
GND pin.
FB2 (Pin 6):
Feedback Pin for Switcher 2. Set the output
voltage by selecting values for R3 and R4.
V
REF
(Pin 7):
Voltage Reference Pin (1.25V). This pin is
used along with FB2 to set the negative output voltage for
Switcher 2.
SHDN2 (Pin 8):
Shutdown Pin for Switcher 2. Pull this pin
above 1.5V to enable Switcher 2. Pull below 0.3V to turn
it off. Do not leave this pin floating.
3463f
U W
V
REF
and V
FB1
Voltage
1.27
10
V
FB2
Voltage
1.26
8
6
1.24
4
1.23
2
1.22
–50 –25
0
25
50
75
100
125
0
–50 –25
TEMPERATURE (°C)
3463 G02
50
25
75
0
TEMPERATURE (°C)
100
125
3463 G03
Switch Current Limit
60
Quiescent Current
LT3463A SW2
350
50
40
30
20
10
NOT SWITCHING
V
FB1
= 1.3V
V
FB2
= –0.1V
50
25
75
0
TEMPERATURE (°C)
100
125
0
–50 –25
TEMPERATURE (°C)
3463 G05
3463 G06
U
U
U
3
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
