LTC3770_15 Datasheet, PDF (3/24 Pages) Linear Technology – Fast No RSENSE Step-Down Synchronous Controller with Margining, Tracking and PLL

LTC3770
ELECTRICAL CHARACTERISTICS The l denotes specifications which apply over the full operating
temperature range, otherwise specifications are T_A = 25°C. V_IN = 15V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX
Main Control Loop
I_Q
Input DC Supply Current
Normal Operation
Shutdown Supply Current
1300 2200
30
50
V_FB
V_FB(LINEREG)
V_FB(LOADREG)
V_RUN
I_SS/TRACK
I_FB
g_m(EA)
V_FCB
I_FCB
t_ON
t_ON(MIN)
t_OFF(MIN)
V_SENSE(MAX)
V_SENSE(MIN)
ΔV_FB(OV)
V_IN(UVLO+)
V_{IN(UVLO–)}
V_MGN(TH)
V_MPGM
TG R_UP
TG R_DOWN
BG R_UP
BG R_DOWN
TG t_r
TG t_f
BG t_r
BG t_f
Feedback Voltage Accuracy (Note 3)
Feedback Voltage Line Regulation
Feedback Voltage Load Regulation
Run Pin On Threshold
Soft-Start Charging Current
Feedback Pin Input Current
V_REFIN = V_REFOUT; I_TH = 1.2V (0°C to 85°C)
0.596
V_REFIN = V_REFOUT; I_TH = 1.2V
l 0.594
V_IN = 4V to 30V, I_TH = 1.2V (Note 3)
I_TH = 0.5V to 1.9V (Note 3)
V_RUN Rising
1
V_SS/TRACK = 0V
–1.1
–100
Error Amplifier Transconductance
Forced Continuous Threshold
I_TH = 1.2V (Note 3)
l
1
l 0.57
Forced Continuous Pin Current
V_FCB = 0V
On-Time
I_ON = –60μA, V_ON = 1.5V
210
I_ON = –60μA, V_ON = 0V
90
Minimum On-Time
I_ON = –180μA, V_ON = 0V
Minimum Off-Time
Tested with a Square Wave (Note 5)
Maximum Current Sense Threshold
V_SENSE– – V_SENSE+
Minimum Current Sense Threshold
V_SENSE– – V_SENSE+
Output Overvoltage Fault Threshold Offset
V_RNG = 1V, V_FB = V_REFIN – 30mV
V_RNG = 0V, V_FB = V_REFIN – 30mV
V_RNG = INTV_CC, V_FB = V_REFIN – 30mV
V_RNG = 1V, V_FB = V_REFIN + 30mV
V_RNG = 0V, V_FB = V_REFIN + 30mV
V_RNG = INTV_CC, V_FB = V_REFIN + 30mV
l 113
l 50
l 228
7
Undervoltage Lockout
V_IN Falling
l
Undervoltage Lockout
V_IN Rising
l
MARGIN0, MARGIN1 Input Thresholds
MPGM Pin Voltage
TG Driver Pull-Up On Resistance
TG High
TG Driver Pull-Down On Resistance
TG Low
BG Driver Pull-Up On Resistance
BG High
BG Driver Pull-Down On Resistance
BG Low
TG Rise Time
TG Fall Time
BG Rise Time
BG Fall Time
C_LOAD = 3300pF
C_LOAD = 3300pF
C_LOAD = 3300pF
C_LOAD = 3300pF
0.6
0.6
0.002
– 0.05
1.5
–1.4
–20
1.3
0.6
–1
250
115
50
250
133
67
268
– 60
–30
–120
10
3.2
3.3
1.4
1.18
1.9
1.2
1.9
0.7
20
20
20
20
0.604
0.606
– 0.3
1.9
–1.7
100
1.6
0.63
–2
290
150
100
400
153
84
308
13
3.9
4
2.5
2.5
3
1.5
UNITS
μA
μA
V
V
%/V
%
V
μA
nA
mS
V
μA
ns
ns
ns
ns
mV
mV
mV
mV
mV
mV
%
V
V
V
V
Ω
Ω
Ω
Ω
ns
ns
ns
ns
3770fc
3