Linear Technology LTC1624, Руководство пользователя

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2
LTC1624
ABSOLUTE M AXI M U M RATINGS
W
W W
U
Input Supply Voltage (V
IN
)......................... 36V to – 0.3V
Topside Driver Supply Voltage (BOOST)....42V to – 0.3V
Switch Voltage (SW).................................. 36V to – 0.6V
Differential Boost Voltage
(BOOST to SW) ....................................7.8V to – 0.3V
SENSE
–
Voltage
V
IN
< 15V .................................. (V
IN
+ 0.3V) to – 0.3V
V
IN
≥
15V .......................... (V
IN
+0.3V) to (V
IN
– 15V)
I
TH
/RUN, V
FB
Voltages ............................ 2.7V to – 0.3V
Peak Driver Output Current < 10
µ
s (TG) .................... 2A
Operating Temperature Range
LTC1624CS ............................................ 0
°
C to 70
°
C
LTC1624IS ......................................... – 40
°
C to 85
°
C
Junction Temperature (Note 1)............................. 125
°
C
Storage Temperature Range ................. – 65
°
C to 150
°
C
Lead Temperature (Soldering, 10 sec).................. 300
°
C
PACKAGE/ORDER I N FOR M ATIO N
W U U
ORDER PART
NUMBER
S8 PART MARKING
TOP VIEW
V
IN
BOOST
TG
SW
SENSE
–
I
TH
/RUN
V
FB
GND
S8 PACKAGE
8-LEAD PLASTIC SO
1
2
3
4
8
7
6
5
T
JMAX
= 125
°
C,
θ
JA
= 110
°
C/ W
LTC1624CS8
LTC1624IS8
1624
1624I
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
T
A
= 25
°
C, V
IN
= 15V, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loop
I
IN
V
FB
Feedback Current (Note 2) 10 50 nA
V
FB
Feedback Voltage (Note 2)
●
1.1781 1.19 1.2019 V
∆
V
LINE REG
Reference Voltage Line Regulation V
IN
= 3.6V to 20V (Note 2) 0.002 0.01 %/V
∆
V
LOAD REG
Output Voltage Load Regulation (Note 2)
I
TH
Sinking 5
µ
A ● 0.5 0.8 %
I
TH
Sourcing 5
µ
A
●
– 0.5 – 0.8 %
V
OVL
Output Overvoltage Lockout 1.24 1.28 1.32 V
I
Q
Input DC Supply Current (Note 3)
Normal Mode 550 900
µ
A
Shutdown V
ITH/RUN
= 0V 16 30
µ
A
V
ITH/RUN
Run Threshold 0.6 0.8 V
I
ITH/RUN
Run Current Source V
ITH/RUN
= 0.3V – 0.8 – 2.5 – 5.0
µ
A
Run Pullup Current V
ITH/RUN
= 1V – 50 –160 – 350
µ
A
∆
V
SENSE(MAX)
Maximum Current Sense Threshold V
FB
= 1.0V 145 160 185 mV
TG Transition Time
TG t
r
Rise Time C
LOAD
= 3000pF 50 150 ns
TG t
f
Fall Time C
LOAD
= 3000pF 50 150 ns
f
OSC
Oscillator Frequency ● 175 200 225 kHz
V
BOOST
Boost Voltage SW = 0V, I
BOOST
= 5mA, V
IN
= 8V 4.8 5.15 5.5 V
∆
V
BOOST
Boost Load Regulation SW = 0V, I
BOOST
= 2mA to 20mA 3 5 %
T
J
= T
A
+ (P
D
• 110
°
C/W)
Note 2: The LTC1624 is tested in a feedback loop which servos V
FB
to
the midpoint for the error amplifier (V
ITH
= 1.8V).
Note 3: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
The ● denotes specifications which apply over the full operating
temperature range.
LTC1624CS: 0
°
C
≤
T
A
≤
70
°
C
LTC1624IS: – 40
°
C
≤
T
A
≤
85
°
C
Note 1: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formula: