LTC3831 Datasheet, PDF (5/20 Pages) Linear Technology – High Power Synchronous Switching Regulator Controller for DDR Memory Termination

TYPICAL PERFOR A CE CHARACTERISTICS
Maximum TG Duty Cycle
vs Temperature
100
V_FB = 0V
99 ^{REFER TO FIGURE 3}
98
97
96
95
94
93
92
91
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
3831 G11
Output Current Limit Threshold
vs Temperature
10
REFER TO FIGURE 1
9
8
7
6
5
4
3
2
1
0
–50 –25
0 25 50 75 100 125
TEMPERATURE (°C)
3831 G14
Undervoltage Lockout Threshold
Voltage vs Temperature
3.0
2.9
2.8
2.7
2.6
2.5
2.4
2.3
2.2
2.1
2.0
–50 –25
0 25 50 75 100 125
TEMPERATURE (°C)
3831 G17
I_MAX Sink Current
vs Temperature
20
18
16
14
12
10
8
6
4
– 50 – 25
0 25 50 75
TEMPERATURE (°C)
100 125
3831 G12
Soft-Start Source Current
vs Temperature
–8
–9
–10
–11
–12
–13
–14
–15
–16
– 50 – 25
0 25 50 75
TEMPERATURE (°C)
100 125
3831 G15
V_CC Operating Supply Current
vs Temperature
1.6
FREQSET FLOATING
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
3831 G18
LTC3831
Output Overcurrent Protection
1.4
1.2
1.0
0.8
0.6
0.4
0.2 _{TA = 25°C}
REFER TO FIGURE 1
0
0
2
4
6
8
OUTPUT CURRENT (A)
10
3831 G13
Soft-Start Sink Current
vs (V_IFB – V_IMAX)
2.00
T_A = 25°C
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0
–150 –125 –100 –75 –50
V_IFB – V_IMAX (mV)
–25 0
3831 G16
PV_CC Supply Current
vs Oscillator Frequency
90
T_A = 25°C
80
70
60
TG AND BG LOADED
WITH 6800pF,
PV_CC1,2 = 12V
50
TG AND BG
40
LOADED
WITH 1000pF,
30
PV_CC1,2 = 5V
TG AND BG
LOADED
WITH 6800pF,
PV_CC1,2 = 5V
20
10
0
0
100 200 300 400 500
OSCILLATOR FREQUENCY (kHz)
3831 G19
3831f
5