LTC3417
3
3417fd
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: The LTC3417 is guaranteed to meet specifi ed performance from
0°C to 85°C. Specifi cations over the –40°C to 85°C operating ambient
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 3: The LTC3417 is tested in feedback loop which servos V
FB1
to the
midpoint for the error amplifi er (V
ITH1
= 0.6V) and V
FB2
to the midpoint for
the error amplifi er (V
ITH2
= 0.6V).
Note 4: Total supply current is higher due to the internal gate charge being
delivered at the switching frequency.
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
IN
= 3.6V unless otherwise specifi ed. (Note 2)
Note 5: Switch on-resistance is guaranteed by design and test correlation
on the DHC package and by fi nal test correlation on the FE package.
Note 6: Variable frequency operation with resistor is guaranteed by design
but not production tested and is subject to duty cycle limitations.
Note 7: This IC 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 specifi ed maximum operating junction
temperature may impair device reliability.
Note 8: T
J
is calculated from the ambient temperature, T
A
, and power dis-
sipation, P
D
, according to the following formula:
LTC3417EDHC: T
J
= T
A
+ (P
D
• 43°C/W)
LTC3417EFE: T
J
= T
A
+ (P
D
• 38°C/W)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
g
m(EA)
Error Amplifi er Transconductance I
TH1
, I
TH2(PINLOAD)
= ±5µA (Note 3) 1400 µS
I
S
Input DC Supply Current (Note 4)
Active Mode V
FB1
= V
FB2
= 0.75V, V
MODE
= V
IN
,
V
RUN1
= V
RUN2
= V
IN
400 600 µA
Half Active Mode (V
RUN2
= 0V, 1.4A Only) V
FB1
= 0.75V, V
MODE
= V
IN
, V
RUN1
= V
IN
260 400 µA
Half Active Mode (V
RUN1
= 0V, 800mA Only) V
FB2
= 0.75V, V
MODE
= V
IN
, V
RUN2
= V
IN
260 400 µA
Both Channels in Sleep Mode V
FB1
= V
FB2
= 1V, V
MODE
= V
IN
,
V
RUN1
= V
RUN2
= V
IN
125 250 µA
Shutdown V
RUN1
= V
RUN2
= 0V 0.1 1 µA
f
OSC
Oscillator Frequency V
FREQ
= V
IN
V
FREQ
: R
T
= 143k
V
FREQ
: Resistor (Note 6)
1.2
0.85
1.5
1
1.8
1.25
4
MHz
MHz
MHz
I
LIM1
Peak Switch Current Limit on SW1 (1.4A) 1.8 2.25 A
I
LIM2
Peak Switch Current Limit on SW2 (800mA) 1 1.2 A
R
DS(ON)1
SW1 Top Switch On-Resistance (1.4A)
SW1 Bottom Switch On-Resistance
V
IN1
= 3.6V (Note 5)
V
IN1
= 3.6V (Note 5)
0.088
0.084
R
DS(ON)2
SW2 Top Switch On-Resistance (800mA)
SW2 Bottom Switch On-Resistance
V
IN2
= 3.6V (Note 5)
V
IN2
= 3.6V (Note 5)
0.16
0.15
I
SW1(LKG)
Switch Leakage Current SW1 (1.4A) V
IN1
= 6V, V
ITH1
= 0V, V
RUN1
= 0V 0.01 1 µA
I
SW2(LKG)
Switch Leakage Current SW2 (800mA) V
IN2
= 6V, V
ITH2
= 0V, V
RUN2
= 0V 0.01 1 µA
V
UVLO
Undervoltage Lockout Threshold V
IN1
, V
IN2
Ramping Down
V
IN1
, V
IN2
Ramping Up
1.9
1.95
2.07
2.12
2.2
2.25
V
V
T
PGOOD
Threshold for Power Good. Percentage
Deviation from V
FB
Steady State
(Typically 0.8V)
V
FB1
or V
FB2
Ramping Up
V
FB1
or V
FB2
Ramping Down
–6
–6
%
%
R
PGOOD
Power Good Pull-Down On-Resistance 160 300
V
RUN1
,
V
RUN2
RUN1, RUN2 Threshold 0.3 0.85 1.5 V
V
PHASE
PHASE Threshold High-CMOS Levels V
IN
–0.5 V
PHASE Threshold Low-CMOS Levels 0.5 V
I
RUN1
, I
RUN2
,
I
PHASE
, I
MODE
RUN1, RUN2, PHASE and MODE
Leakage Current
V
IN
= 6V, V
PIN
= 3V 0.01 1 µA
VTL
MODE
MODE Threshold Voltage Low 0.5 V
VTH
MODE
MODE Threshold Voltage High V
IN
–0.5 V
VTH
FREQ
FREQ Threshold Voltage High V
IN
–0.5 V
