Datasheet

LTC3217
3
3217fa
TYPICAL PERFORMANCE CHARACTERISTICS
ELECTRICAL CHARACTERISTICS
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: Based on charge pump long-term current density limitations.
Assumes an operating duty cycle of ≤10% under absolute maximum
conditions for durations less than 10 seconds. Maximum current for
continuous operation is 300mA.
Note 3: Based on LED current source long-term current density
limitations. Assumes an operating duty cycle of ≤10% under absolute
CPO Short Circuit Detection
Threshold Voltage
●
0.4 1.3 V
Test Current CPO = 0V, EN1 = EN2 = Low
●
10 30 mA
Unused LED Detection
Threshold Voltage V
CPO
– LED
●
0.5 1.5 V
Test Current LED Tied to CPO
●
416μA
EN1, EN2
Low Level Input Voltage (V
IL
)
●
0.4 V
High Level Input Voltage (V
IH
)
●
1.4 V
Input Current (I
IH
)
●
730μA
Input Current (I
IL
)
●
–1 1 μA
Minimum PWM On-Time EN2 Only
●
50 μs
Maximum PWM Off-Time EN2 to Remain Enabled, EN1 = Low
●
1ms
I
SET1
, I
SET2
V
ISET1
,
ISET2
I
LED1-4
= 12.5mA
●
1.175 1.215 1.255 V
I
ISET1
,
ISET2
Current Range
●
31.25 375 μA
I
ISET1
,
ISET2
Short-Circuit Current 800 μA
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
BAT
= 3.6V, C1 = C2 = C3 = C4 = 2.2μF, unless otherwise noted.
LED Dropout Voltage
vs LED Current
LED Pin Current
vs LED Pin Voltage
I
LED
vs R
ISET
T
A
= 25°C unless otherwise noted.
maximum conditions for durations less than 10 seconds. Maximum
current for continuous operation is 100mA.
Note 4: The LTC3217E is guaranteed to meet performance specifi cations
from 0°C to 85°C. Specifi cations over the –40°C to 85°C ambient
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 5: 1.5x mode output impedance is defi ned as (1.5V
BAT
– V
CPO
)/I
OUT
.
2x mode output impedance is defi ned as (2V
BAT
– V
CPO
)/I
OUT
.
LED CURRENT (mA)
10
0
LED DROPOUT VOLTAGE (mV)
100
200
300
400
20 30 40 50
3217 G01
60 70 80 90 100
V
BAT
= 3.6V
LED PIN VOLTAGE (V)
0
0
LED PIN CURRENT (mA)
20
40
60
80
100
120
0.2 0.4 0.6 0.8
3217 G02
1.0
V
BAT
= 3.6V
R
ISET
(kΩ)
0
I
LED
(mA)
40
80
120
20
60
100
10 20 30 40
3217 G03
505015253545