LTC3789_15 Datasheet, PDF (4/30 Pages) Linear Technology – High Efficiency, Synchronous, 4-Switch Buck-Boost Controller

LTC3789
Electrical Characteristics The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T_A = 25°C (Note 2). V_IN = 15V, V_RUN = 5V, unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
INTV_CC Linear Regulator
V_INTVCCVIN
Internal V_CC Voltage
V_LDOVIN
INTV_CC Load Regulation
V_INTVCCEXT
Internal V_CC Voltage
V_LDOEXT
INTV_CC Load Regulation
V_EXTVCC
EXTV_CC Switchover Voltage
V_LDOHYS
EXTV_CC Hysteresis
Oscillator and Phase-Locked Loop
6.5V < V_IN < 40V, V_EXTVCC = 0V
I_CC = 0mA to 20mA, V_EXTVCC = 0V
6.5V < V_EXTVCC < 14V
I_CC = 0mA to 20mA, V_EXTVCC = 12V
I_CC = 0mA to 20mA, EXTV_CC Ramping Positive
5.2 5.5 5.8
V
0.2 1.0
%
5.2 5.5 5.8
V
0.2 1.0
%
4.7 4.8
V
0.25
V
f_NOM
f_LOW
f_HIGH
f_SYNC
R_MODE/PLLIN
I_FREQ
PGOOD Output
Nominal Frequency
Low Fixed Frequency
High Fixed Frequency
Synchronizable Frequency
MODE/PLLIN Input Resistance
Frequency Setting Current
V_FREQ = 1.2V
V_FREQ = 0V
V_FREQ = 2.4V
MODE/PLLIN = External Clock
350 400 440
kHz
175 200 225
kHz
570 640 710
kHz
l 200
600
kHz
220
kΩ
8
10 12
µA
V_PGL
I_PGOOD
V_PG
PGOOD Voltage Low
PGOOD Leakage Current
PGOOD Trip Level
I_PGOOD = 2mA
V_PGOOD = 5V
V_FB with Respect to Set Output Voltage
V_FB Ramping Negative
V_FB Ramping Positive
0.1 0.3
V
±1
µA
–10
%
10
%
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 LTC3789 is tested under pulse load conditions such that
T_J ≈ T_A. The LTC3789E is guaranteed to meet performance specifications
from 0°C to 85°C operating 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 LTC3789I is guaranteed to meet performance specifications over the
full –40°C to 125°C operating junction temperature range.
Note 3: T_J is calculated from the ambient temperature T_A and power
dissipation P_D according to the following formula:
LTC3789GN: T_J = T_A + (P_D • 80°C/W)
LTC3789UFD: T_J = T_A + (P_D • 34°C/W)
Note 4: The LTC3789 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 the Applications Information
section.
Note 6: Do not apply a voltage or current to these pins. They must be
connected to capacitive loads only, otherwise permanent damage may
occur.
3789fc
4
For more information www.linear.com/LTC3789