LTC3859AL Datasheet, PDF (9/44 Pages) Linear Technology – Triple Output, Buck/Buck/Boost Synchronous Controller with 28μA Burst Mode IQ

Typical Performance Characteristics
LTC3859AL
INTV_CC Line Regulation
5.5
5.4
5.3
5.2
5.1
5.0
0
5 10 15 20 25 30 35 40
INPUT VOLTAGE (V)
3859al G19
SENSE Pins Total Input Current
vs V_SENSE Voltage
800
700
SENSE1, 2 PINS
600
500
400
300
200
SENSE3 PIN
100
0
0 5 10 15 20 25 30 35 40
V_SENSE COMMON MODE VOLTAGE (V)
3859al G22
Maximum Current Sense
Threshold vs Duty Cycle
80
70
60
50
BUCK
40
BOOST
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
DUTY CYCLE (%)
3859al G25
INTV_CC and EXTV_CC
vs Load Current
5.6
5.4
EXTV_CC = 8.5V
5.2
EXTV_CC = 0V
5.0
4.8
EXTV_CC = 5V
4.6
4.4
4.2
V_BIAS = 12V
4.0
0
20
40
60
80 100
LOAD CURRENT (mA)
3859al G20
Buck SENSE^– Pin Input Bias
Current vs Temperature
900
800
V_OUT > INTV_CC + 0.5V
700
600
500
400
300
200
100
0
V_OUT < INTV_CC – 0.5V
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3859al G23
Maximum Current Sense
Threshold vs I_TH Voltage
60
50
40
30
20
10
0
–10
–20
–30
0
PULSE-SKIPPING
FORCED CONTINUOUS
Burst Mode OPERATION
0.2 0.4 0.6 0.8 1 1.2 1.4
I_TH (V)
3859al G26
For more information www.linear.com/3859AL
EXTV_CC Switchover and INTV_CC
Voltages vs Temperature
6.0
5.8
5.6
5.4
INTV_CC
5.2
5.0
4.8
EXTV_CC RISING
4.6
4.4
EXTV_CC FALLING
4.2
4.0
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3859al G21
Boost SENSE Pin Total Input
Current vs Temperature
200
V_IN = 12V
180
160
SENSE3⁺ PIN
140
120
100
80
60
40
20
0
–75 –50 –25 0
SENSE3^– PIN
25 50 75 100 125 150
TEMPERATURE (°C)
3859al G24
TRACK/SS Pull-Up Current
vs Temperature
6.00
5.75
5.50
5.25
5.00
4.75
4.50
4.25
4.00
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3859al G27
3859alf
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