English
Language : 

LTC3883 Datasheet, PDF (9/112 Pages) Linear Technology – Single Phase Step-Down DC/DC Controller with Digital Power System Management
◁
LTC3883/LTC3883-1
Electrical Characteristics
less than the minimum endurance specification. The RESTORE_USER_ALL
command (NVM read) is valid over the entire operating temperature range.
Note 14: The LTC3883-1 quiescent current (IQ) equals the IQ of VIN plus
the IQ of EXTVCC.
Note 15: The LTC3883 includes overtemperature protection that is
intended to protect the device during momentary overload conditions.
Junction temperature will exceed 125°C when overtemperature protection
is active. Continuous operation above the specified maximum operating
junction temperature may impair device reliability.
Typical Performance Characteristics
Efficiency vs Load Current,
VOUT = 1.8V (LTC3883)
100
90
80
70
60
50
40
30
20
10
0
0.01
VIN = 12V
VOUT = 1.8V
fSW = 350kHz
L = 0.56µH
DCR = 1.8mΩ
CCM
DCM
BM
0.1
1
10
100
LOAD CURRENT (A)
3883 G01
Load Step
(Burst Mode Operation)
Efficiency vs Load Current,
VOUT = 3.3V (LTC3883)
100
90
80
70
60
50
40
30
20
10
0
0.01
VIN = 12V
VOUT = 3.3V
fSW = 350kHz
L = 0.56µH
DCR = 1.8mΩ
CCM
DCM
BM
0.1
1
10
100
LOAD CURRENT (A)
3883 G02
Load Step
(Forced Continuous Mode)
Efficiency and Power Loss
vs Input Voltage (LTC3883)
92
4.0
90
3.5
88
3.0
86
2.5
84
2.0
82
1.5
80
5
10
15
20
VIN (V)
1.0
25
3883 G03
Load Step
(Pulse-Skipping Mode)
ILOAD
5A/DIV
INDUCTOR
CURRENT
5A/DIV
VOUT
100mV/DIV
AC-COUPLED
VIN = 12V
50µs/DIV
VOUT = 1.8V
0.3A TO 5A STEP
ILOAD
5A/DIV
INDUCTOR
CURRENT
5A/DIV
VOUT
100mV/DIV
AC-COUPLED
3883 G04
VIN = 12V
50µs/DIV
VOUT = 1.8V
0.3A TO 5A STEP
ILOAD
5A/DIV
INDUCTOR
CURRENT
5A/DIV
VOUT
100mV/DIV
AC-COUPLED
3883 G05
VIN = 12V
50µs/DIV
VOUT = 1.8V
0.3A TO 5A STEP
3883 G06
Inductor Current at Light Load
Start-Up into a Pre-Biased Load
Soft-Start Ramp
FORCED
CONTINUOUS
MODE
2A/DIV
Burst Mode
OPERATION
2A/DIV
PULSE-SKIPPING
MODE
2A/DIV
VIN = 12V
VOUT = 1.8V
ILOAD = 100µA
1µs/DIV
RUN
2V/DIV
VOUT
1V/DIV
3883 G07
tRISE = 10ms
tDELAY = 5ms
VOUT = 2V
5ms/DIV
RUN
2V/DIV
VOUT
1V/DIV
3883 G08
tRISE = 10ms
tDELAY = 5ms
5ms/DIV
3883 G09
3883f
9
 ▷