LTC3731H_15 Datasheet, PDF (3/34 Pages) Linear Technology – 3-Phase, 600kHz, Synchronous Buck Switching Regulator Controller

LTC3731H
Electrical Characteristics The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_CC = V_RUN/SS = 5V unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX UNITS
Main Control Loop
V_REGULATED Regulated Voltage at EAIN
V_ITH = 1.2V (Note 3)
0.594 0.600 0.606
V
l 0.590 0.600 0.614
V
V_SENSEMAX Maximum Current Sense Threshold
I_MATCH
V_LOADREG
Maximum Current Threshold Match
Output Voltage Load Regulation
V_REFLNREG
g_m
g_mOL
V_FCB
I_FCB
V_BINHIBIT
UVR
UVADJ
Output Voltage Line Regulation
Transconductance Amplifier g_m
Transconductance Amplifier GBW
Forced Continuous Threshold
FCB Bias Current
Burst Inhibit Threshold
Undervoltage RUN/SS Reset
Undervoltage Lockout Threshold
VV_ESAEINNSE=₁0_–,.5VVS,_EV_NISTEH2O_–,pVeSn_E,_{NSE3– = 0.6V, 1.8V}
65
75
85
mV
l 60
75
90
mV
Worst-Case Error at V_SENSEMAX
–5
5
%
(Note 3)
Measured in Servo Loop, ∆I_TH Voltage = 1.2V to 0.7V l
Measured in Servo Loop, ∆I_TH Voltage = 1.2V to 2V l
0.1
0.7
%
–0.1
–0.7
%
V_CC = 4.5V to 7V
0.03
%/V
I_TH = 1.2V, Sink/Source 25µA (Note 3)
l
3
5
7 mmho
I_TH = 1.2V (g_m • Z_L, Z_L = Series 1k – 100kΩ – 1nF)
3
MHz
l 0.54
0.60
0.66
V
V_FCB = 0.65V
Measured at FCB Pin
V_CC Lowered Until the RUN/SS Pin is Pulled Low
0.2
0.7
µA
V_CC – 1.5 V_CC – 0.7 V_CC – 0.3
V
3.3
3.8
4.5
V
1.13
1.18
1.23
V
I_UVADJ
I_Q
Undervoltage Bias Current
Input DC Supply Current
Normal Mode
Shutdown
I_RUN/SS
Soft-Start Charge Current
V_RUN/SS RUN/SS Pin ON Threshold
V_RUN/SSARM RUN/SS Pin Arming Threshold
At UVADJ Threshold
(Note 4)
V_CC = 5V
V_RUN/SS = 0V
V_RUN/SS = 1.9V
V_RUN/SS, Ramping Positive
V_RUN/SS, Ramping Positive Until Short-Circuit
Latch-Off is Armed
0.2
50
nA
2.3
3.5
mA
50
100
µA
–0.8
–1.5
–2.5
µA
1
1.5
1.9
V
3.8
4.5
V
V_RUN/SSLO
I_SCL
I_SDLHO
I_SENSE
RUN/SS Pin Latch-Off Threshold
RUN/SS Discharge Current
Shutdown Latch Disable Current
SENSE Pins Source Current
V_RUN/SS, Ramping Negative
Soft-Short Condition V_EAIN = 0.375V, V_RUN/SS = 4.5V
V_EAIN = 0.375V, V_RUN/SS = 4.5V
SENSE1⁺, SENSE1^–, SENSE2⁺, SENSE2^–, SENSE3⁺,
SENSE3^– All Equal 1.2V; Current at Each Pin
3.2
V
–5
–1.5
µA
1.5
5
µA
13
20
µA
DF_MAX
TG t_R, t_F
BG t_R, t_F
TG/BG t_1D
Maximum Duty Factor
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
In Dropout, V_SENSEMAX ≤ 30mV
C_LOAD = 3300pF
C_LOAD = 3300pF
C_LOAD = 3300pF
C_LOAD = 3300pF
All Controllers, C_LOAD = 3300pF Each Driver
95
98.5
%
30
90
ns
40
90
ns
30
90
ns
20
90
ns
50
ns
BG/TG t_2D Bottom Gate Off to Top Gate On Delay All Controllers, C_LOAD = 3300pF Each Driver
Top Switch-On Delay Time
60
ns
t_ON(MIN)
Minimum On-Time
Tested with a Square Wave (Note 5)
110
ns
3731Hfb