Datasheet

4
LTC3445
3445fa
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LTC3445EUF is guaranteed to meet performance specifica-
tions from 0°C to 70°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
ELECTRICAL CHARACTERISTICS
Note 3: T
J
is calculated from the ambient temperature, T
A
, and power
dissipation, P
D
, according to the following formula:
T
J
= T
A
+ P
D
• 37°C/W
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 5: Determined by design, not production tested.
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC1
= V
CC2
= 3.6V, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
t
SU(RSTA)
Repeated Start Condition Setup Time (Note 5) 600 ns
t
SU(STOP)
Stop Condition Setup Time (Note 5) 600 ns
t
HD(DIN)
Data Hold Time, Input (Note 5) 0 ns
t
SU(DAT)
Data Setup Time (Note 5) 100 ns
V
THR
SCL and SDA Logic Input Threshold 1.8 V
V
HYS
SCL and SDA Logic Input Hysteresis (Note 5) 50 mV
I
LVTRACK
V
TRACK
Leakage V
CC
= 3.6V 1.44 2.2 µA
I
LVBACKUP
V
BACKUP
Leakage V
CC
= 3.6V ● 1 µA
I
LADD7
ADD7 Leakage V
CC
= 3.6V ● 1 µA
I
LADD6
ADD6 Leakage V
CC
= 3.6V ● 1 µA
I
LSCL
SCL Leakage V
CC
= 3.6V ● 1 µA
I
LSDA
SCL Leakage V
CC
= 3.6V ● 1 µA
I
LLDO1
LDO1 Leakage V
CC
= 3.6V, RUN = 0 ● 1 µA
I
LLDO2
LDO2 Leakage V
CC
= 3.6V, RUN = 0 ● 1 µA
I
LLDO1FB
LDO1FB Leakage V
CC
= 3.6V, RUN = 0 ● 1 µA
I
LLDO2FB
LDO2FB Leakage V
CC
= 3.6V, RUN = 0 ● 1 µA
I
LBATTFAULT
BATTFAULT Leakage V
CC
= 3.6V ● 1 µA
I
FB1,2
LDO Feedback Input Current V
FB1
= 0.6V ● 1 µA
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Supply Current vs Supply Voltage
SUPPLY VOLTAGE (V)
2.4
SUPPLY CURRENT (µA)
300
400
500
3.6 4.4 5.6
3445 G01
200
100
0
2.8 3.2
4
4.8 5.2
ALL ON
BUCK
TWO LDOs
RUN = HIGH
RUN = LOW
ONE LDO
V
OUT
vs DAC
DAC VALUE
0
V
OUT
(V)
1.2
1.4
80
3445 G02
1.0
0.8
20
40
60
10
30
50
70
1.6
1.1
1.3
0.9
1.5
0mA
600mA
DAC VALUE
0
V
OUT(N)
– V
OUT(N–1)
(V)
0.008
0.010
0.012
80
3445 G03
0.006
0.004
–0.002
20
40
60
10
30
50
70
0.002
0
0.016
0.014
100mA
V
OUT
Step Size vs DAC