LTC3784_15 Datasheet, PDF (7/38 Pages) Linear Technology – 60V PolyPhase Synchronous Boost Controller

LTC3784
Typical Performance Characteristics T_A = 25°C unless otherwise noted.
Oscillator Frequency
vs Temperature
600
FREQ = INTV_CC
550
500
450
400
FREQ = GND
350
300
–60 –35 –10 15 40 65 90
TEMPERATURE (°C)
115 140
3784 G19
SENSE Pin Input Current
vs Temperature
260
240
220
V_SENSE = 12V
I_LIM = FLOAT
200
SENSE⁺ PIN
180
160
140
120
100
80
60
40
20
SENSE ^– PIN
0
–60 –35 –10 15 40 65 90 115 140
TEMPERATURE (°C)
3784 G22
Maximum Current Sense
Threshold vs Duty Cycle
120
100 ^{ILIM = INTVCC}
80 ILIM = FLOAT
60
I_LIM = GND
40
20
0
0 10 20 30 40 50 60 70 80 90 100
DUTY CYCLE (%)
3784 G25
Oscillator Frequency
vs Input Voltage
360
FREQ = GND
358
356
354
352
350
348
346
344
342
340
5 10 15 20 25 30 35 40 45 50 55 60 65
INPUT VOLTAGE (V)
3784 G20
SENSE Pin Input Current
vs I_TH Voltage
260
240 ^{VSENSE = 12V}
I_LIM = INTV_CC
220
200 _SENSE+ _PIN
180
I_LIM = FLOAT
I_LIM = GND
160
140
120
100
80
60
40
20 _{SENSE – PIN}
0
I_LIM = INTV_CC
I_LIM = FLOAT
I_LIM = GND
0 0.5 1 1.5 2 2.5 3
I_TH VOLTAGE (V)
3784 G23
Charge Pump Charging Current
vs Operating Frequency
80
T = –60°C
70
60
T = –45°C
50
T = 25°C
40
T = 130°C
30
T = 155°C
20
10
0
50 150 250 350 450 550 650 750
OPERATING FREQUENCY (kHz)
3784 G26
Maximum Current Sense
Threshold vs I_TH Voltage
120
100
80
PULSE-SKIPPING MODE
60
Burst Mode
OPERATION
40
20
0
I_LIM = GND
I_LIM = FLOAT
–20
I_LIM = INTV_CC
–40 ^{FORCED CONTINUOUS MODE}
–60
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4
I_TH VOLTAGE (V)
3784 G21
SENSE Pin Input Current
vs V_SENSE Voltage
260
240 SENSE⁺ PIN
I_LIM = INTV_CC
220
I_LIM = FLOAT
200
180
I_LIM = GND
160
140
120
100
80
60
I_LIM = INTV_CC
40
I_LIM = FLOAT
20 _SENSE– _PIN
I_LIM = GND
0
5 10 15 20 25 30 35 40 45 50 55 60 65
VSENSE COMMON MODE VOLTAGE (V)
3784 G24
Charge Pump Charging Current
vs Switch Voltage
70
FREQ = GND
60
FREQ = INTV_CC
50
40
30
20
10
0
5 15 25 35 45 55 65
SWITCH VOLTAGE (V)
3784 G27
For more information www.linear.com/LTC3784
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