LT8391AE .......................................... –40°C to 125°C
LT8391AI ........................................... –40°C to 125°C
LT8391AH .......................................... –40°C to 150°C
Storage Temperature Range .................. –65°C to 150°C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
BST1
BST2
CTRL2
SW1
SW2
22 TG2
21 V
OUT
20 PWMTG
29
GND
19 SYNC/SPRD
18 RT
17 V
C
16 FB
15 SS
9 10 11 12 13 14
V
REF
CTRL1
ISP
ISN
FAULT
BG1
BG2
28 BG2
27 BST2
26 SW2
25 TG2
24 V
OUT
23 PWMTG
22 SYNC/SPRD
21 RT
20 V
C
19 FB
18 SS
17
FAULT
16 CTRL2
15 ISN
BG1
BST1
SW1
TG1
LSP
LSN
V
IN
INTV
CC
EN/UVLO
1
2
3
4
5
6
7
8
9
29
GND
28 27 26 25 24 23
TG1 1
LSP 2
LSN 3
V
IN
4
INTV
CC
5
EN/UVLO 6
RP 7
PWM 8
RP 10
PWM 11
V
REF
12
CTRL1 13
ISP 14
FE PACKAGE
28-LEAD PLASTIC TSSOP
θ
JA
= 30°C/W,
θ
JC
= 5°C/W
EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB
UFD PACKAGE
28-LEAD (4mm
×
5mm) PLASTIC QFN
θ
JA
= 34°C/W,
θ
JC
= 3.4°C/W
EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
(http://www.linear.com/product/LT8391A#orderinfo)
LEAD FREE FINISH
LT8391AEFE#PBF
LT8391AIFE#PBF
LT8391AHFE#PBF
LT8391AEUFD#PBF
LT8391AIUFD#PBF
LT8391AHUFD#PBF
TAPE AND REEL
LT8391AEFE#TRPBF
LT8391AIFE#TRPBF
LT8391AHFE#TRPBF
LT8391AEUFD#TRPBF
LT8391AIUFD#TRPBF
LT8391AHUFD#TRPBF
PART MARKING*
LT8391AFE
LT8391AFE
LT8391AFE
8391A
8391A
8391A
PACKAGE DESCRIPTION
28-Lead Plastic TSSOP
28-Lead Plastic TSSOP
28-Lead Plastic TSSOP
28-Lead (4mm × 5mm) Plastic QFN
28-Lead (4mm × 5mm) Plastic QFN
28-Lead (4mm × 5mm) Plastic QFN
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/.
Some packages are available in 500 unit reels through
designated sales channels with #TRMPBF suffix.
8391af
2
For more information
www.linear.com/LT8391A
LT8391A
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 2). V
IN
= 12V, V
EN/UVLO
= 1.5V unless otherwise noted.
SYMBOL PARAMETER
V
IN
Operating Voltage Range
V
IN
Quiescent Current
V
OUT
Voltage Range
V
OUT
Quiescent Current
Linear Regulators
INTV
CC
Regulation Voltage
INTV
CC
Load Regulation
INTV
CC
Line Regulation
INTV
CC
Current Limit
INTV
CC
Dropout Voltage (V
IN
– INTV
CC
)
INTV
CC
Undervoltage Lockout Threshold
INTV
CC
Undervoltage Lockout Hysteresis
V
REF
Regulation Voltage
V
REF
Load Regulation
V
REF
Line Regulation
V
REF
Current Limit
V
REF
Undervoltage Lockout Threshold
V
REF
Undervoltage Lockout Hysteresis
Control Inputs/Outputs
EN/UVLO Shutdown Threshold
EN/UVLO Enable Threshold
EN/UVLO Enable Hysteresis
EN/UVLO Hysteresis Current
V
EN/UVLO
= 0.3V
V
EN/UVLO
= 1.1V
V
EN/UVLO
= 1.3V
V
CTRL1/2
= 0.75V (Note 4), Current out of
Pin
Falling
l
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
l
MIN
4
TYP
1
270
2.1
MAX
60
2
2.8
60
0.5
0.5
60
5.15
4
4
190
3.64
2.03
1
0.2
3.2
1.90
UNITS
V
µA
µA
mA
V
µA
µA
µA
V
%
%
mA
mV
V
V
V
%
%
mA
V
mV
V
EN/UVLO
= 0.3V
V
EN/UVLO
= 1.1V
Not Switching
l
0
0.1
0.1
40
5.0
1
1
110
3.44
145
160
3.54
0.24
2.00
0.4
0.1
2
1.78
2.5
1.84
50
0.3
1.196
–0.1
2.2
–0.1
0
190
0.6
1.220
13
0
2.5
0
20
200
28
V
EN/UVLO
= 0.3V, V
OUT
= 12V
V
EN/UVLO
= 1.1V, V
OUT
= 12V
Not Switching, V
OUT
= 12V
I
INTVCC
= 20mA
I
INTVCC
= 0mA to 80mA
I
INTVCC
= 20mA, V
IN
= 6V to 60V
V
INTVCC
= 4.5V
I
INTVCC
= 20mA, V
IN
= 4V
Falling
I
VREF
= 100µA
I
VREF
= 0mA to 1mA
I
VREF
= 100µA, V
IN
= 4V to 60V
V
REF
= 1.8V
Falling
l
20
4.85
1.97
1.0
1.244
0.1
2.8
0.1
50
210
V
V
mV
µA
µA
µA
nA
mV
mV
Falling
l
CTRL1, CTRL2 Input Bias Current
CTRL1, CTRL2 Dim-Off Threshold
CTRL1, CTRL2 Dim-Off Hysteresis
PWM Dimming
External PWM Dimming Threshold
External PWM Dimming Hysteresis
Internal PWM Dimming Duty Cycle
Rising, R
P
= 30k
R
P
= 30k
V
PWM
= 1V, R
P
≥ 51k
V
PWM
= 1.5V, R
P
≥ 51k
V
PWM
= 2V, R
P
≥ 51k
R
P
= 51k
R
P
= 82k
R
P
= 130k
R
P
= 200k
R
P
= 300k
l
1.3
1.4
220
1.5
3
53
V
mV
%
%
%
47
97
256
512
1024
2048
4096
Switching Frequency to Internal PWM Dimming
Frequency Ratio
8391af
For more information
www.linear.com/LT8391A
3
LT8391A
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 2). V
IN
= 12V, V
EN/UVLO
= 1.5V unless otherwise noted.
SYMBOL PARAMETER
RP Pin Current Limit
Minimum V
OUT
for PWMTG to be On
PWMTG On Voltage V
(VOUT-PWMTG)
PWMTG Off Voltage V
(VOUT-PWMTG)
PWM to PWMTG Turn On Propagation Delay
PWM to PWMTG Turn Off Propagation Delay
PWMTG Turn On Fall Time
PWMTG Turn Off Rise Time
Error Amplifier
Full Scale LED Current Regulation V
(ISP-ISN)
9/10th LED Current Regulation V
(ISP-ISN)
1/2 LED Current Regulation V
(ISP-ISN)
1/20th LED Current Regulation V
(ISP-ISN)
Zero Scale LED Current Regulation V
(ISP-ISN)
ISP/ISN Input Common Mode Range
ISP/ISN Low Side to High Side Switchover
Voltage
ISP/ISN High Side to Low Side Switchover
Voltage
ISP Input Bias Current
V
ISP
= V
ISN
V
ISP
= V
ISN
V
PWM
= 5V, V
ISP
= V
ISN
= 12V
V
PWM
= 5V, V
ISP
= V
ISN
= 0V
V
EN/UVLO
= 0V, V
ISP
= V
ISN
= 12V or 0V
V
PWM
= 5V, V
ISP
= V
ISN
= 12V
V
PWM
= 5V, V
ISP
= V
ISN
= 0V
V
EN/UVLO
= 0V, V
ISP
= V
ISN
= 12V or 0V
V
C
= 1.2V
V
IN
= 4V to 60V
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
V
RP
= 0V, Current out of Pin
PWM dimming on
V
OUT
= 12V
V
OUT
= 12V
C
PWMTG
= 3.3nF to V
OUT
, 50% to 50%
C
PWMTG
= 3.3nF to V
OUT
, 50% to 50%
C
PWMTG
= 3.3nF to V
OUT
, 10% to 90%
C
PWMTG
= 3.3nF to V
OUT
, 90% to 10%
V
CTRL1/2
≥ 1.35V (Note 4), V
ISP
= 12V
V
CTRL1/2
≥ 1.35V (Note 4), V
ISP
= 0V
V
CTRL1/2
= 1.15V (Note 4), V
ISP
= 12V
V
CTRL1/2
= 1.15V (Note 4), V
ISP
= 0V
V
CTRL1/2
= 0.75V (Note 4), V
ISP
= 12V
V
CTRL1/2
= 0.75V (Note 4), V
ISP
= 0V
V
CTRL1/2
= 0.30V (Note 4), V
ISP
= 12V
V
CTRL1/2
= 0.30V (Note 4), V
ISP
= 0V
V
CTRL1/2
= 0.25V (Note 4), V
ISP
= 12V
V
CTRL1/2
= 0.25V (Note 4), V
ISP
= 0V
l
l
l
l
l
l
l
l
l
l
l
MIN
TYP
40
2.4
MAX
3
5.5
0.1
UNITS
µA
V
V
V
ns
ns
ns
ns
4.5
–0.1
5
0
90
40
300
10
97
97
87
87
47.5
47.5
3
3
–2
–2
0
100
100
90
90
50
50
5
5
0
0
1.8
1.7
23
–10
0
23
–10
0
2000
103
103
93
93
52.5
52.5
7
7
2
2
60
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
V
V
V
µA
µA
µA
µA
µA
µA
µS
ISN Input Bias Current
LED Current Regulation Amplifier g
m
FB Regulation Voltage
FB Line Regulation
FB Load Regulation
FB Voltage Regulation Amplifier g
m
FB Input Bias Current
V
C
Output Impedance
V
C
Standby Leakage Current
V
C
= 1.2V, PWM Dimming Off
–10
FB in Regulation, Current Out of Pin
0.98
1.00
0.2
0.2
660
10
10
0
1.02
0.5
0.8
40
10
V
%
%
µS
nA
MΩ
nA
8391af
4
For more information
www.linear.com/LT8391A
LT8391A
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
当今的计算机外部设备,都在追求高速度和高通用性。为了满足用户的需求,以Intel为首的七家公司于1994年推出了USB(Universal Serial Bus,通用串行总线)总线协议,专用于低、中速的计算机外设。目前,USB端口已成为微机主板的标准端口;而在不久的将来,所有的微机外设,包括键盘、鼠标、显示器、打印机、数字相机、扫描仪和游戏柄等等,都将通过USB与主机相连。
...[详细]