Linear Technology Analog Devices LT8708, Техническое описание

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LT8708
9
Rev 0
For more information www.analog.com
TYPICAL PERFORMANCE CHARACTERISTICS
Efficiency vs Output Current
(Boost Region – Page 59)
Efficiency vs Output Current
(Buck Region – Page 59)
Efficiency vs Output Current
(Buck–Boost Region – Page 59)
Feedback Voltages Feedback Voltages (Five Parts) Oscillator Frequency
Maximum Inductor Current Sense
Voltage vs Duty Cycle
Inductor Current Sense Voltage at
Minimum Duty Cycle
Maximum Inductor Current Sense
Voltage at Minimum Duty Cycle
LOAD CURRENT (A)
0.01 0.1 1 10
0
10
20
30
40
50
60
70
80
90
100
EFFICIENCY (%)
8708 G01
HCM
DCM
CCM
V
IN
= 38V
V
OUT
= 47.4V
LOAD CURRENT (A)
0.01 0.1 1 10
0
10
20
30
40
50
60
70
80
90
100
EFFICIENCY (%)
8708 G02
HCM
DCM
CCM
V
IN
= 51.5V
V
OUT
= 47.4V
LOAD CURRENT (A)
0.01 0.1 1 10
0
10
20
30
40
50
60
70
80
90
100
EFFICIENCY (%)
8708 G03
HCM
DCM
CCM
V
IN
= 48V
V
OUT
= 47.4V
V
C
= 1.2V
FBOUT
FBIN
IMON_INP
IMON_INN
IMON_ON
IMON_OP
TEMPERATURE (°C)
–45 –20 5 30 55 80 105 130 155
1.17
1.18
1.19
1.20
1.21
1.22
1.23
PIN VOL
TAGE (V)
Feedback Voltages
8708 G04
V
C
= 1.2V
TEMPERATURE (°C)
–45 –20 5 30 55 80 105 130 155
1.17
1.18
1.19
1.20
1.21
1.22
1.23
PIN VOL
TAGE (V)
8708 G05
R
T
= 124k
R
T
= 215k
R
T
= 365k
TEMPERATURE (°C)
–45 –20 5 30 55 80 105 130 155
0
50
100
150
200
250
300
350
400
FREQUENCY (kHz)
Oscillator Frequency
8708 G06
BUCK REGION
BOOST REGION
M2 OR M3 DUTY CYCLE (%)
0 20 40 60 80 100
0
20
40
60
80
100
120
140
|CSP–CSN| (mV)
8708 G07
BUCK REGION
BOOST REGION
V
C
(V)
0.5 1 1.5 2
–100
–80
–60
–40
–20
0
20
40
60
80
100
–100
–80
–60
–40
–20
0
20
40
60
80
100
CSN–CSP (mV)
CSP–CSN (mV)
8708 G08
BUCK REGION
BOOST REGION
TEMPERATURE (°C)
–45 –20 5 30 55 80 105 130 155
0
20
40
60
80
100
120
|CSP–CSN| (mV)
Voltage at Minimum Duty Cycle
8708 G09