LTC3728LCGN-PBF Datasheet, PDF (5/38 Pages) Linear Technology – Dual, 550kHz, 2-Phase Synchronous Regulators

LTC3728L/LTC3728LX
Electrical Characteristics The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_IN = 15V, V_{RUN/SS1, 2} = 5V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
INTV_CC Linear Regulator
V_INTVCC
Internal V_CC Voltage
V_LDO INT
INTV_CC Load Regulation
V_LDO EXT
EXTV_CC Voltage Drop
V_EXTVCC
EXTV_CC Switchover Voltage
V_LDOHYS
EXTV_CC Hysteresis
Oscillator and Phase-Locked Loop
6V < V_IN < 30V, V_EXTVCC = 4V
I_CC = 0 to 20mA, V_EXTVCC = 4V
I_CC = 20mA, V_EXTVCC = 5V
I_CC = 20mA, EXTV_CC Ramping Positive
4.8 5.0 5.2
V
0.2 2.0
%
100 200
mV
● 4.5 4.7
V
0.2
V
f_NOM
f_LOW
f_HIGH
R_PLLIN
I_PLLFLTR
Nominal Frequency
Lowest Frequency
Highest Frequency
PLLIN Input Resistance
Phase Detector Output Current
Sinking Capability
Sourcing Capability
3.3V Linear Regulator
V_PLLFLTR = 1.2V
V_PLLFLTR = 0V
V_PLLFLTR ≥ 2.4V
f_PLLIN < f_OSC
f_PLLIN > f_OSC
360 400 440
kHz
230 260 290
kHz
480 550 590
kHz
50
kΩ
–15
µA
15
µA
V_3.3OUT
3.3V Regulator Output Voltage
V_3.3IL
3.3V Regulator Load Regulation
V_3.3VL
3.3V Regulator Line Regulation
PGOOD Output
No Load
I_3.3 = 0 to 10mA
6V < V_IN < 30V
● 3.2 3.35 3.45
V
0.5
2
%
0.05 0.2
%
V_PGL
I_PGOOD
V_PG
PGOOD Voltage Low
PGOOD Leakage Current
PGOOD Trip Level, Either Controller
I_PGOOD = 2mA
V_PGOOD = 5V
V_OSENSE with Respect to Set Output Voltage
V_OSENSE Ramping Negative
V_OSENSE Ramping Positive
0.1 0.3
V
±1
µA
– 6 –7.5 – 9.5
%
6 7.5 9.5
%
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 according to the following formulas:
LTC3728LUH/LTC3728LXUH: T_J = T_A + (P_D • 34°C/W)
LTC3728LGN: T_J = T_A + (P_D • 95°C/W)
Note 3: The IC is tested in a feedback loop that servos V_{ITH1, 2} to a
specified voltage and measures the resultant V_{OSENSE1, 2.}
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See the Applications Information
section.
Note 5: Rise and fall times are measured using 10% and 90% levels. Delay
times are measured using 50% levels.
Note 6: The minimum on-time is tested under an ideal condition without
external power FETs. It can be larger when the IC is operating in an
actual circuit. See Minimum On-Time Considerations in the Applications
Information section.
Note 7: The LTC3728LC/LTC3728LXC are guaranteed to meet performance
specifications from 0°C to 85°C. The LTC3728LE is guaranteed to meet
performance specifications over the –40°C to 85°C operating temperature
range as assured by design, characterization and correlation with statistical
process controls. The LTC3728LI is guaranteed to meet performance
specifications over the –40°C to 85°C operating temperature range.
Note 8: Guaranteed by design.
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