Datasheet

LTC3735
4
3735fa
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
PVCC
= 5V, V
RUN/SS
= 5V unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Oscillator
I
FREQSET
FREQSET Input Current V
FREQSET
= 0V –2 –1 µA
f
NOM
Nominal Frequency V
FREQSET
= 1.2V 320 355 390 kHz
f
LOW
Lowest Frequency V
FREQSET
= 0V 190 210 240 kHz
f
HIGH
Highest Frequency V
FREQSET
≥ 2.4V 490 550 610 kHz
PGOOD Output
V
PGL
PGOOD Voltage Low I
PGOOD
= 2mA 0.1 0.3 V
I
PGOOD
PGOOD Leakage Current V
PGOOD
= 5V ±1 µA
V
PG
PGOOD Trip Thresholds V
FB
with Respect to Set Output Voltage
V
FB
Ramping Negative
V
FB
Ramping Positive
–7
7
–10
11
–13
13
%
%
t
MASK
PGOOD Mask Timer 100 110 120 µs
t
DELAY
MCH_PG Delay Time 15 cycles
Operational Amplifier
I
B
Input Bias Current 15 200 nA
V
OS
Input Offset Voltage Magnitude V
OA
+ = V
OA
– 1.2V, I
OUT
= 1mA 0.8 5 mV
CM Common Mode Input Voltage Range 0 P
VCC
– 1.4 V
CMRR Common Mode Rejection Ratio I
OUT
= 1mA 46 70 dB
I
CL
Output Source Current 10 35 mA
A
VOL
Open-Loop DC Gain I
OUT
= 1mA 30 V/mV
GBP Gain-Bandwidth Product I
OUT
= 1mA 2 MHz
SR Slew Rate R
L
= 2k 5 V/µs
V
O(MAX)
Maximum High Output Voltage I
OUT
= 1mA P
VCC
– 1.2 P
VCC
– 0.9 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: The LTC3735E is guaranteed to meet performance specifications
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.
Note 3: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formula:
LTC3735EG: T
J
= T
A
+ (P
D
• 85°C/W)
LTC3735EUHF: T
J
= T
A
+ (P
D
• 34°C/W)
Note 4: The LTC3735 is tested in a feedback loop that servos V
ITH
to a
specified voltage and measures the resultant V
FB
.
Note 5: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
Note 6: Rise and fall times are measured using 10% and 90% levels. Delay
times are measured using 50% levels.
Note 7: The minimum on-time condition corresponds to the on inductor
peak-to-peak ripple current ≥40% I
MAX
(see Minimum On-Time
Considerations in the Applications Information section).
Note 8: The ATTEN
ERR
specification is in addition to the output voltage
accuracy specified at VID code = 010110.