LTC3789_15 Datasheet, PDF (3/30 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
V_IN
V_OUT
V_FB
I_FB
V_REFLNREG
V_LOADREG
g_m
I_Q
UVLO
UVLO Hyst
II^{SSEENNSSEE+–}
II^{IIOOSSEENNSSEE+–}
I_SS
V_RUN(ON)
V_RUN(HYS)
I_RUN
I_RUN(HYS)
V_SENSE(MAX)
V_SENSE(IAVG)
R_DSPFET(ON)
R_DSNFET(ON)
TG t_r
TG t_f
BG t_r
BG t_f
TG/BG t_1D
Input Supply Voltage
Output Voltage
Regulated Feedback Voltage
Feedback Current
Reference Voltage Line Regulation
Output Voltage Load Regulation
Transconductance Amplifier g_m
Input DC Supply Current
Normal Mode
Shutdown
Undervoltage Lockout
Undervoltage Hysteresis
SENSE Pins Current
I_TH Voltage = 1.2V (Note 4), T_A = –40°C to 85°C
I_TH = 1.2V, T_A = 125°C, T_A = –40°C to 125°C
(Note 4)
V_IN = 4V to 38V (Note 4)
(Note 4)
Measured in Servo Loop, ∆I_TH Voltage = 1.4V to 2V
Measured in Servo Loop, ∆I_TH Voltage = 2V to 2.5V
I_TH = 1.2V, Sink/Source 5µA (Note 4)
(Note 5)
V_RUN = 0V
INTV_CC Ramping Down
V_SENSE– = V_SENSE+ = 0V
I_OSENSE Pins Current
V_{IOSENSE–} = V_IOSENSE+ = 10V
Soft-Start Charge Current
RUN Pin On-Threshold
RUN Pin On-Hysteresis
RUN Pin Source Current
RUN Pin Hysteresis Current
Maximum Current Sense Threshold
Buck Region, (I_L Valley)
Boost Region, (I_L Peak)
Maximum Input/Output Average
Current Sense Threshold
Driver Pull-Up On-Resistance
Driver Pull-Down On-Resistance
Top Gate Rise Time
Top Gate Fall Time
Bottom Gate Rise Time
Bottom Gate Fall Time
Top Gate Off to Bottom Gate On
Delay Synchronous Switch-On
Delay Time
V_SS = 0V
V_RUN Rising
V_FB = 0.7V
V_FB = 0.7V
I_LIM = 0V
I_LIM Floating
I_LIM = INTV_CC
C_LOAD = 3300pF Each Driver (Note 6)
4
38
V
0.8
38
V
l 0.792 0.800 0.808
V
l 0.788 0.800 0.812
V
–15 –50
nA
0.002 0.02 %/V
l
0.01 0.1
%
l
–0.01 –0.1
%
1.5
mmho
3
mA
40 60
µA
3.4 3.6
V
0.4
V
0.2 ±1
µA
10 14
µA
2
3
4
µA
1.22
V
150
mV
1.2
µA
5
µA
l 73 90 107
mV
l 123 140 157
mV
48 50 52.5
mV
90 100 106
mV
130 145 160
mV
2.6
Ω
1.5
Ω
25
ns
25
ns
25
ns
25
ns
60
ns
BG/TG t_1D
Bottom Gate Off to Top Gate On
Delay Top Switch-On Delay Time
C_LOAD = 3300pF Each Driver (Note 6)
60
ns
DF_MAX,BOOST
D_{ON(MIN,BOOST)}
Maximum Duty Factor
Minimum Duty Factor for Main
Switch in Boost Operation
% Switch C On
% Switch C On
90
%
9
%
D_ON(MIN,BUCK)
Minimum Duty Factor for
Synchronous Switch in Buck
Operation
% Switch B On
9
%
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