LTC3770
4
3770fc
ELECTRICAL CHARACTERISTICS
The l denotes specifi cations which apply over the full operating
temperature range, otherwise specifi cations are T
A
= 25°C. V
IN
= 15V unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Internal V
CC
Regulator
V
INTVCC
Internal V
CC
Voltage 6V < V
IN
< 30V
l
4.7 5 5.3 V
ΔV
LDO(LOADREG)
Internal V
CC
Load Regulation I
CC
= 0mA to 20mA –0.1
±2
%
Phased-Locked Loop
R
PLLIN
PLLIN Input Resistance 50 kΩ
I
PLLFLTR
Phase Detector Output Current
Sink Capability
Source Capability
f
PLLIN
< f
0
f
PLLIN
> f
0
–15
15
μA
μA
PGOOD Output
ΔV
FBH
PGOOD Upper Threshold V
FB
Rising 7 10 13 %
ΔV
FBL
PGOOD Lower Threshold V
FB
Falling –7 –10 –13 %
ΔV
FB(HYS)
PGOOD Hysteresis V
FB
Returning 1.5 3 %
V
PGL
PGOOD Low Voltage I
PGOOD
= 5mA 0.15 0.4 V
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: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
as follows:
LTC3770EG: T
J
= T
A
+ (P
D
• 130°C/W)
LTC3770EUH: T
J
= T
A
+ (P
D
• 34°C/W)
Note 3: The 3770 is tested in a feedback loop that adjusts V
FB
to
achieve a specifi ed error amplifi er output voltage (I
TH
). For these tests,
V
REFOUT
= V
REFIN
.
Note 4: The LTC3770E is guaranteed to meet performance specifi cations
from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 5: The minimum off-time condition is specifi ed for large peak-to-peak
inductor ripple current (see Minimum Off-Time Considerations in
the Applications Information section).
TYPICAL PERFORMANCE CHARACTERISTICS
I
TH
VOLTAGE (V)
0
–200
CURRENT SENSE THRESHOLD (mV)
–100
0
100
200
300
0.5
1.0 1.5 2.0
3770 G01
2.5 3.0
V
RNG
=
1V
0.7V
0.5V
1.4V
2V
I
ON
CURRENT (μA)
1
10
ON-TIME (ns)
100
1000
10000
10 100
3770 G02
V
VON
= 0V
V
ON
VOLTAGE (V)
0
ON-TIME (ns)
400
600
3770 G03
200
0
1
2
543
1200
1000
800
I
ION
= 60μA
Current Sense Threshold
vs I
TH
Voltage On-Time vs I
ON
Current On-Time vs V
ON
Voltage
