LTC3355
4
3355fb
For more information www.linear.com/LTC3355
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V unless otherwise noted. (Note 2)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
5A Boost Regulator
I
VOUT
V
OUT
Quiescent Current V
OUT
= 3.3V, No Load, In Regulation, No
Switching, Burst Mode
l
80 160 280 µA
I
SW2
SW2 Peak Current R
IBSTPK
= 200k, PWM Mode
R
IBSTPK
= 200k, Burst Mode
4.5 5
1.5
5.5 A
A
R
NMOS
NMOS On-Resistance 70 mΩ
I
LEAKN
NMOS Leakage Current Boost Disabled –5 5 µA
DC Max Boost Maximum Duty Cycle 88 92 98 %
V
SBOOST
Boost Input Supply Voltage Range 0.75 5 V
Boost
Minimum Input Supply V
OUT(MAX)
= 4V 0.5 V
A
V
Boost Error Amplifier Voltage Gain (Note 5) 850 V/V
g
m
Boost Error Amplifier Transconductance 27 μS
V
IBSTPK
I
BSTPK
Reference Voltage 0.775 0.825 V
R
IBSTPK
I
BSTPK
Set Resistor Range 200 1000 kΩ
Logic (MODE, EN_CHG, CPGOOD, RSTB, PFOB)
V
IL
Input Low Logic Voltage MODE, EN_CHG 0.4 V
V
IH
Input High Logic Voltage MODE, EN_CHG 1.2 V
I
IL
, I
IH
Input Low/High Current MODE, EN_CHG -1 1 µA
V
OL
Output Logic Low Voltage PFOB, CPGOOD, RSTB; Sink 100µA 50 mV
I
OH
Logic High Leakage Current PFOB, CPGOOD, RSTB; 5V 1 µA
CPGOOD Rising Threshold V
CAP
as a % of Final Target 90 92.5 95 %
CPGOOD Hysteresis ∆V
CAP
as a % of Final Value 2.5 %
RSTB Falling Threshold V
OUT
as a % of Final Target 90 92.5 95 %
RSTB Hysteresis ∆V
OUT
as a % of Final Value 2.5 %
RSTB Delay 250 ms
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: The LTC3355 is tested under pulsed load conditions such that
T
J
≈ T
A
. The LTC3355E is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to
125°C operating junction temperature
range are assured by design,
characterization and correlation with statistical process controls. The
LTC3355I is guaranteed over the –40°C to 125°C operating junction
temperature range. Note that the maximum ambient temperature
consistent with these specifications is determined by specific operating
conditions in conjunction with board layout, the rated package thermal
impedance and other environmental factors. The junction temperature
(T
J
, in °C) is calculated from the ambient temperature (T
A
, in °C) and
power dissipation (P
D
, in Watts) according to the formula:
T
J
= T
A
+ (P
D
• θ
JA
)
where θ
JA
= 47°C/W for the UF package.
Note 3: The LTC3355 has a thermal regulation loop that limits the
maximum junction temperature to 110°C by limiting the charger current.
Note 4: The current limit features of this part are intended to protect the
IC from short-term or intermittent fault conditions. Continuous operation
above the maximum specified pin current may
result in device degradation
or failure.
Note 5: Guaranteed by design and/or correlation to static test.
Note 6: The LTC3355 has a thermal shutdown that will shut down the part
when the die temperature reaches 155°C.
