LTC3808 Datasheet, PDF (5/28 Pages) Linear Technology – No RSENSE TM, Low EMI, Synchronous DC/DC Controller with Output Tracking

LTC3808
TYPICAL PERFOR A CE CHARACTERISTICS T_A = 25°C unless otherwise noted.
Start-Up with Coincident Tracking
(V_OUT = 0V at 0s)
Start-Up with Coincident Tracking
(V_OUT = 0.8V at 0s)
Start-Up with Ratiometric
Tracking (V_OUT = 0V at 0s)
V_x
2.5V
V_OUT
1.8V
V_x
2.5V
V_OUT
1.8V
500mV/DIV
500mV/DIV
V_x
2.5V
V_OUT
1.8V
500mV/DIV
10ms/DIV
V_IN = 4.2V
R_TA = 590Ω
R_TB = 1.18k
FIGURE 11 CIRCUIT
3808 G09
10ms/DIV
V_IN = 4.2V
R_TA = 590Ω
R_TB = 1.18k
FIGURE 11 CIRCUIT
3808 G10
10ms/DIV
V_IN = 4.2V
R_TA = 590Ω
R_TB = 1.69k
FIGURE 11 CIRCUIT
3808 G11
Regulated Feedback Voltage vs
Temperature
0.606
0.604
0.602
0.600
0.598
0.596
0.594
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80 100
3808 G12
Undervoltage Lockout Threshold
vs Temperature
2.55
2.50
V_IN RISING
2.45
2.40
2.35
2.30
V_IN FALLING
2.25
2.20
2.15
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80 100
3808 G13
Shutdown (RUN) Threshold vs
Temperature
1.20
1.15
1.10
1.05
1.00
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80 100
3808 G14
Maximum Current Sense
Threshold vs Temperature
135 _{IPRG = FLOAT}
130
125
120
TRACK/SS Start-Up Current vs
Temperature
1.04
TRACK/SS = 0V
1.02
1.00
0.98
0.96
115
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80 100
3808 G16
0.94
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80 100
3808 G17
3808f
5