LTC3706 Datasheet, PDF (3/20 Pages) Linear Technology – Secondary-Side Synchronous Forward Controller with PolyPhase Capability

LTC3706
ELECTRICAL CHARACTERISTICS The l indicates specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_CC = 7V, V_IN = 15V, GND = PGND = 0V, unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Main Control Loop
V_FB
Regulated Feedback Voltage
(Note 4) ITH = 1.2V
l 0.594 0.600 0.606
V
I_FB
Feedback Input Current
(Note 4)
2
100
nA
ΔV_FB(LINREG)
Feedback Voltage Line Regulation
V_IN = 6V to 30V, ITH = 1.2V
0.001
%/V
ΔV_FB(LOADREG)
Feedback Voltage Load Regulation
Measured in Servo Loop,
ITH = 0.5V to 2V
l
–0.01 –0.1
%
V_ISMAX
V_ISOC
Maximum Current Sense Threshold
Over-Current Shutdown Threshold
R_SENSE Mode, 0V < V_IS– < 5V
V_IS– = V_CC, 0V < V_IS+ < 2V (CT Mode)
R_SENSE Mode, 0V < V_IS– < 5V
V_IS– = V_CC, 0V < V_IS+ < 2V (CT Mode)
68
78
88
mV
1.15 1.28
1.4
V
87
100
113
mV
1.45 1.65 1.85
V
g_m
Transconductance Amplifier gm
2.40 2.75 3.10
mS
I_RUN/SS(C)
Soft-Start Charge Current
V_RUN/SS = 2V
–4
–5
–6
μA
I_RUN/SS(D)
V_RUN/SS
t_ON,MIN
FG, SG R_UP
FG, SG R_DOWN
PT⁺, PT^– R_UP
PT⁺, PT^– R_DOWN
ΔV_FB(OV)
V_CC Supply
Soft-Start Discharge Current
RUN/SS Pin ON Threshold
Minimum ON Time
V_RUN/SS Rising
FG, SG Driver Pull-Up On Resistance FG, SG Low
FG, SG Driver Pull-Down On Resistance
PT⁺, PT^– Driver Pull-Up Resistance
PT⁺, PT^– Driver Pull-Down Resistance
FG, SG High
PT⁺, PT^– Low
PT⁺, PT^– High
Output Overvoltage Threshold
V_FB Rising
3
μA
l 0.4
0.45
0.5
V
200
ns
1.5
2.3
Ω
1.5
2.3
Ω
1.5
2.3
Ω
1.5
2.3
Ω
15
17
19
%
V_CCOP
V_CCREG
I_CC
V_UVLO
V_HYS
V_IN Supply
V_INOP
Operating Voltage Range
Regulated Output Voltage
Supply Current
Operating
Shutdown
UV Lockout
UV Hysteresis
Operating Voltage Range
f_OSC = 200kHz (Note 5)
V_RUN/SS = GND
V_CC Rising
5
10
V
6.6
7.0
7.4
V
4.2
mA
240
μA
l 4.52 4.60 4.70
V
0.4
V
5
30
V
I_IN
V_INUVLO
Supply Current
Normal Mode
Shutdown
UV Lockout
f_OSC = 200kHz
V_RUN/SS = GND
V_IN Rising
900
μA
460
μA
l 3.90 4.30 4.51
V
V_INHYS
V_REGSD
g_m,REGSD
REGSD Shutdown Threshold
REGSD Transconductance
V_REGSD Rising
0.2
V
4
V
5
μS
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