LTC3851A_15 Datasheet, PDF (7/30 Pages) Linear Technology – Synchronous Step-Down Switching Regulator Controller

Typical Performance Characteristics
LTC3851A
Shutdown (RUN) Threshold
vs Temperature
1.4
1.3
RUN RISING THRESHOLD (ON)
1.2
RUN FALLING THRESHOLD (OFF)
1.1
1.0
0.9
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3851A G20
Oscillator Frequency
vs Input Voltage
420
R_FREQ = 80k
415
410
405
400
395
390
385
380
5
10 15 20 25 30 35 40
INPUT VOLTAGE (V)
3851A G23
Shutdown Input DC Supply
Current vs Temperature
40
35
30
25
20
15
10
5
0
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3851A G26
Regulated Feedback Voltage
vs Temperature
806
804
802
800
798
796
794
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3851A G21
Undervoltage Lockout Threshold
(INTV_CC) vs Temperature
5
4
INTV_CC RAMPING UP
3
INTV_CC RAMPING DOWN
2
1
0
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3851A G24
Input DC Supply Current
vs Temperature
3.0
2.5
2.0
1.5
1.0
0.5
0
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3851A G27
Oscillator Frequency
vs Temperature
900
800
R_PLLLPF = 36k
700
600
R_PLLLPF = 60k
500
400
300
R_PLLLPF = 160k
200
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3851A G22
Shutdown Input DC Supply
Current vs Input Voltage
40
35
30
25
20
15
10
5
0
0 5 10 15 20 25 30 35 40
INPUT VOLTAGE (V)
3851A G25
Maximum Current Sense
Threshold vs INTV_CC Voltage
90
80
I_SET = INTV_CC
70
60
I_SET = FLOAT
50
40
I_SET = GND
30
20
10
0
3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0
INTV_CC VOLTAGE(V)
3851A G28
3851afa
7