LTC3707 Datasheet, PDF (3/32 Pages) Linear Technology – High Effi ciency, 2-Phase Synchronous Step-Down Switching Regulator

LTC3707
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
g_{mGBW1, 2}
I_Q
Transconductance Amplifier GBW
Input DC Supply Current
Normal Mode
Standby
Shutdown
V_FCB
I_FCB
V_BINHIBIT
Forced Continuous Threshold
Forced Continuous Pin Current
Burst Inhibit (Constant Frequency)
Threshold
UVLO
Undervoltage Lockout
V_OVL
I_SENSE
V_{STBYMD MS}
V_STBYMD KA
DF_MAX
I_{RUN/SS1, 2}
V_{RUN/SS1, 2} ON
V_{RUN/SS1, 2} LT
Feedback Overvoltage Lockout
Sense Pins Total Source Current
Master Shutdown Threshold
Keep-Alive Power On-Threshold
Maximum Duty Factor
Soft-Start Charge Current
RUN/SS Pin ON Threshold
RUN/SS Pin Latchoff Arming
Threshold
I_{SCL1, 2}
RUN/SS Discharge Current
I_SDLHO
V_SENSE(MAX)
Shutdown Latch Disable Current
Maximum Current Sense Threshold
CONDITIONS
I_{TH1, 2} = 1.2V; (Note 4)
(Note 5)
EXTV_CC Tied to V_OUT1 = 5V
V_{RUN/SS1, 2} = 0V, V_STBYMD > 2V
V_{RUN.SS1, 2} = 0V, V_STBYMD = Open
V_FCB = 0.85V
Measured at FCB pin
V_IN Ramping Down
Measured at V_{OSENSE1, 2}
(Each Channel); V_SENSE1–_{, 2}– = V_SENSE1+_{, 2}+ = 0V
V_STBYMD Ramping Down
V_STBYMD Ramping Up, RUN_{SS1, 2} = 0V
In Dropout
V_{RUN/SS1, 2} = 1.9V
V_RUN/SS1, V_RUN/SS2, Rising
V_RUN/SS1, V_RUN/SS2, Rising from 3V
Soft Short Condition V_{OSENSE1, 2} = 0.5V;
V_{RUN/SS1, 2} = 4.5V
V_{OSENSE1, 2} = 0.5V
V_{OSENSE1, 2} = 0.7V, V_OSENSE1–_{, 2}– = 5V
TG1, 2 t_r
TG1, 2 t_f
BG1, 2 t_r
BG1, 2 t_f
TG/BG t_1D
TG Transition Time:
Rise Time
Fall Time
BG Transition Time:
Rise Time
Fall Time
Top Gate Off to Bottom Gate On Delay
Synchronous Switch-On Delay Time
BG/TG t_2D
Bottom Gate Off to Top Gate On Delay
Top Switch-On Delay Time
t_ON(MIN)
Minimum On-Time
INTV_CC Linear Regulator
V_INTVCC
Internal V_CC Voltage
V_LDO INT
INTV_CC Load Regulation
V_LDO EXT
V_EXTVCC
V_LDOHYS
Oscillator
EXTV_CC Voltage Drop
EXTV_CC Switchover Voltage
EXTV_CC Hysteresis
f_OSC
Oscillator Frequency
f_LOW
Lowest Frequency
(Note 6)
C_LOAD = 3300pF
C_LOAD = 3300pF
(Note 6)
C_LOAD = 3300pF
C_LOAD = 3300pF
C_LOAD = 3300pF Each Driver
C_LOAD = 3300pF Each Driver
Tested with a Square Wave (Note 7)
6V < V_IN < 30V, V_EXTCC = 4V
I_CC = 0 to 20mA, V_EXTVCC = 4V
I_CC = 20mA, V_EXTVCC = 5V
I_CC = 20mA, EXTV_CC Ramping Positive
V_FREQSET = Open (Note 8)
V_FREQSET = 0V
MIN TYP MAX UNITS
3
MHz
350
μA
125
μA
20 35 μA
l 0.76 0.800 0.84
V
–0.30 –0.18 –0.1 μA
4.3 4.8
V
l
3.5
4
V
l 0.84 0.86 0.88
V
–90 –60
μA
0.4
0.6
V
1.5
2
V
98
99.4
%
0.5
1.2
μA
1.0
1.5 2.0
V
4.1 4.75
V
0.5
2
4
μA
65
l 62
1.6
5
μA
75 85 mV
75 88 mV
60 110 ns
60 110 ns
50 110 ns
50 100 ns
80
ns
80
ns
180
ns
4.8
l 4.5
5.0 5.2
V
0.2 2.0
%
100 200 mV
4.7
V
0.2
V
190 220 250 kHz
120 140 160 kHz
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