Linear Technology LTC3350, Руководство пользователя

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LTC3350
5
3350fc
For more information www.linear.com/LTC3350
elecTrical characTerisTics
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2). V
IN
= V
OUT
= 12V, V
DRVCC
= V
INTVCC
unless otherwise
noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
DC
MAX
Maximum Duty Cycle Step-Down Mode
Step-Up Mode
97
87
98
93
99.5 %
%
Gate Drivers
R
UP-TG
TGATE Pull-Up On-Resistance 2 Ω
R
DOWN-TG
TGATE Pull-Down On-Resistance 0.6 Ω
R
UP-BG
BGATE Pull-Up On-Resistance 2 Ω
R
DOWN-BG
BGATE Pull-Down On-Resistance 0.6 Ω
t
r-TG
TGATE 10% to 90% Rise Time C
LOAD
= 3.3nF 18 25 ns
t
f-TG
TGATE 10% to 90% Fall Time C
LOAD
= 3.3nF 8 15 ns
t
r-BG
BGATE 10% to 90% Rise Time C
LOAD
= 3.3nF 18 25 ns
t
f-BG
BGATE 10% to 90% Fall Time C
LOAD
= 3.3nF 8 15 ns
t
NO
Non-Overlap Time 50 ns
t
ON(MIN)
85 ns
INTV
CC
Linear Regulator
V
INTVCC
Internal V
CC
Voltage 5.2V ≤ V
IN
≤ 35V 5 V
∆
V
INTVCC
Load Regulation I
INTVCC
= 50mA –1.5 –2.5 %
PowerPath/Ideal Diodes
V
FTO
Forward Turn-On Voltage 65 mV
V
FR
Forward Regulation 30 mV
V
RTO
Reverse Turn Off –30 mV
t
IF(ON)
INFET Rise Time INFET – V
IN
> 3V, C
INFET
= 3.3nF 560 µs
t
IF(OFF)
INFET Fall Time INFET – V
IN
< 1V, C
INFET
= 3.3nF 1.5 µs
t
OF(ON)
OUTFET Rise Time OUTFET – V
CAP
> 3V, C
OUTFET
= 3.3nF 0.13 µs
t
OF(OFF)
OUTFET Fall Time OUTFET – V
CAP
< 1V, C
OUTFET
= 3.3nF 0.26 µs
Power-Fail Comparator
V
PFI(TH)
PFI Input Threshold (Falling Edge)
l
1.147 1.17 1.193 V
V
PFI(HYS)
PFI Hysteresis 30 mV
I
PFI
PFI Input Leakage Current V
PFI
= 0.5V
l
–50 50 nA
V
PFO
PFO Output Low Voltage I
SINK
= 5mA 200 mV
I
PFO
PFO High-Z Leakage Current V
PFO
= 5V
l
1 μA
PFI Falling to PFO Low Delay 85 ns
PFI Rising to PFO High Delay 0.4 μs
CAPGD
V
CAPFB(TH)
CAPGD Rising Threshold as % of Regulated V
CAP
Feedback Voltage
V
capfb_dac
= Full Scale (1111b)
l
90 92 94 %
V
CAPFB(HYS)
CAPGD Hysteresis at CAPFB as a % of Regulated
V
CAP
Feedback Voltage
V
capfb_dac
= Full Scale (1111b) 1.25 %
V
CAPGD
CAPGD Output Low Voltage I
SINK
= 5mA 200 mV
I
CAPGD
CAPGD High-Z Leakage Current V
CAPGD
= 5V
l
1 μA