型号
  • 型号
  • 关键词
首页 > 器件类别 >

LT8705_15

80V VIN and VOUT Synchronous 4-Switch Buck- Boost DC/DC Controller

厂商名称：Linear ( ADI )

厂商官网：http://www.analog.com/cn/index.html

下载文档
预览
文档预览
LT8705
80V V
IN
and V
OUT
Synchronous 4-Switch Buck-
Boost DC/DC Controller
FeaTures
n
n
n
n
n
n
n
n
DescripTion
The
LT
®
8705
is a high performance buck-boost switch-
ing regulator controller that operates from input voltages
above, below or equal to the output voltage. The part has
integrated input current, input voltage, output current
and output voltage feedback loops. With a wide 2.8V to
80V input and 1.3V to 80V output range, the LT8705 is
compatible with most solar, automotive, telecom and
battery-powered systems.
The LT8705 includes servo pins to indicate which feedback
loops are active. The MODE pin selects among Burst Mode
®
operation, discontinuous or continuous conduction mode
at light loads. Additional features include a 3.3V/12mA
LDO, a synchronizable fixed operating frequency, onboard
gate drivers, adjustable UVLO, along with input and output
current monitoring with programmable maximum levels.
L,
LT, LTC, LTM, Linear Technology, Burst Mode, µModule and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
n
n
Single Inductor Allows V
IN
Above, Below, or Equal
to Regulated V
OUT
V
IN
Range 2.8V (Need EXTV
CC
> 6.4V) to 80V
V
OUT
Range: 1.3V to 80V
Quad N-Channel MOSFET Gate Drivers
Synchronous Rectification: Up to 98% Efficiency
Input and Output Current Monitor Pins
Synchronizable Fixed Frequency: 100kHz to 400kHz
Integrated Input Current, Input Voltage, Output Cur-
rent and Output Voltage Feedback Loops
Clock Output Usable To Monitor Die Temperature
Available in 38-Lead (5mm
×
7mm) QFN and TSSOP
Packages with the TSSOP Modified for Improved
High Voltage Operation
applicaTions
n
n
High Voltage Buck-Boost Converters
Input or Output Current Limited Converters
Typical applicaTion
Telecom Voltage Stabilizer
V
IN
36V TO
80V
+
M1
×2
220µF
×2
4.7µF
×4
M2
TO
DIODE
0.22µF
2
×2
TG1 BOOST1 SW1 BG1 CSP
CSNIN
CSPIN
V
IN
100k
SHDN
SWEN
LDO33
MODE
FBIN
RT
1nF
1nF
22µH
M3
×2
10
10
M4
4.7µF
×6
+
TO
DIODE
0.22µF
V
OUT
48V
220µF 5A
×2
10m
2
×2
392k
100
Efficiency and Power Loss
6
5
95
POWER LOSS (W)
EFFICIENCY (%)
4
90
3
2
85
V
OUT
= 48V
I
LOAD
= 2A
30
40
50
60
V
IN
(V)
70
80
8705 TA01b
CSN
GND BG2 SW2 BOOST2 TG2
CSPOUT
CSNOUT
EXTV
CC
FBOUT
INTV
CC
10k
4.7µF
4.7µF
4
GATEV
CC
SRVO_FBIN
SRVO_FBOUT
SRVO_IIN
SRVO_IOUT
IMON_IN
IMON_OUT
TO
TO
BOOST1 BOOST2
LT8705
1
0
71.5k
1µF
20k
4.7µF
215k
SS
80
V
C
56.2k
1µF
220pF
3.3nF
CLKOUT
202kHz
SYNC
8705 TA01
8705fe
For more information
www.linear.com/LT8705
1
LT8705
absoluTe MaxiMuM raTings
(Note 1)
V
CSP
-V
CSN
, V
CSPIN
-V
CSNIN
,
V
CSPOUT
-V
CSNOUT
...................................... –0.3V to 0.3V
SS, CLKOUT, CSP, CSN Voltage ................... –0.3V to 3V
V
C
Voltage (Note 2) ................................... –0.3V to 2.2V
RT, LDO33, FBOUT Voltage .......................... –0.3V to 5V
IMON_IN, IMON_OUT Voltage ..................... –0.3V to 5V
SYNC Voltage............................................ –0.3V to 5.5V
INTV
CC
, GATEV
CC
Voltage ............................ –0.3V to 7V
V
BOOST1
-V
SW1
, V
BOOST2
-V
SW2
..................... –0.3V to 7V
SWEN, MODE Voltage .................................. –0.3V to 7V
SRVO_FBIN, SRVO_FBOUT Voltage ........... –0.3V to 30V
SRVO_IIN, SRVO_IOUT Voltage ................. –0.3V to 30V
FBIN,
SHDN
Voltage ................................... –0.3V to 30V
CSNIN, CSPIN, CSPOUT, CSNOUT Voltage ..–0.3V to 80V
V
IN
, EXTV
CC
Voltage .................................. –0.3V to 80V
SW1, SW2 Voltage ......................................81V (Note 7)
BOOST1, BOOST2 Voltage ......................... –0.3V to 87V
BG1, BG2, TG1, TG2 ........................................... (Note 6)
Operating Junction Temperature Range
LT8705E (Notes 3, 8) ......................... –40°C to 125°C
LT8705I (Notes 3, 8) .......................... –40°C to 125°C
LT8705H (Notes 3, 8)......................... –40°C to 150°C
LT8705MP (Notes 3, 8)...................... –55°C to 150°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
FE Package ....................................................... 300°C
pin conFiguraTion
TOP VIEW
TOP VIEW
IMON_IN
INTV
CC
CSNIN
CSPIN
MODE
SWEN
V
IN
INTV
CC
MODE
IMON_IN
SHDN
31 CSPOUT
30 CSNOUT
29 EXTV
CC
28 SRVO_FBOUT
27 SRVO_IOUT
39
GND
26 SRVO_IIN
25 SRVO_FBIN
24 NC
23 BOOST1
22 TG1
21 SW1
20 NC
13 14 15 16 17 18 19
BG2
BOOST2
TG2
GATEV
CC
SW2
GND
BG1
CSN
CSP
LDO33
FBIN
FBOUT
1
2
3
4
5
6
7
8
9
39
GND
30
EXTV
CC
28
BOOST1
26
TG1
24
SW1
22
SW2
21
TG2
20
BOOST2
32
CSNOUT
34
CSPOUT
38
V
IN
37
CSPIN
36
CSNIN
38 37 36 35 34 33 32
SHDN
1
CSN 2
CSP 3
LDO33 4
FBIN 5
FBOUT 6
IMON_OUT 7
V
C
8
SS 9
CLKOUT 10
SYNC 11
RT 12
IMON_OUT
10
V
C
11
SS
12
CLKOUT
13
SYNC
14
RT
15
GND
16
BG1
17
GATEV
CC
18
BG2
19
UHF PACKAGE
38-LEAD (5mm
×
7mm) PLASTIC QFN
T
JMAX
= 125°C,
θ
JA
= 34°C/W
EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB
FE PACKAGE
VARIATION: FE38(31)
38-LEAD PLASTIC TSSOP
T
JMAX
= 125°C,
θ
JA
= 25°C/W
EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB
2
8705fe
For more information
www.linear.com/LT8705
LT8705
orDer inForMaTion
LEAD FREE FINISH
LT8705EUHF#PBF
LT8705IUHF#PBF
LT8705EFE#PBF
LT8705IFE#PBF
LT8705HFE#PBF
LT8705MPFE#PBF
TAPE AND REEL
LT8705EUHF#TRPBF
LT8705IUHF#TRPBF
LT8705EFE#TRPBF
LT8705IFE#TRPBF
LT8705HFE#TRPBF
LT8705MPFE#TRPBF
PART MARKING*
8705
8705
LT8705FE
LT8705FE
LT8705FE
LT8705FE
PACKAGE DESCRIPTION
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead Plastic TSSOP
38-Lead Plastic TSSOP
38-Lead Plastic TSSOP
38-Lead Plastic TSSOP
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
–55°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/
elecTrical characTerisTics
PARAMETER
Voltage Supplies and Regulators
V
IN
Operating Voltage Range
V
IN
Quiescent Current
V
IN
Quiescent Current in Shutdown
EXTV
CC
Switchover Voltage
EXTV
CC
Switchover Hysteresis
INTV
CC
Current Limit
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V,
SHDN
= 3V unless otherwise noted. (Note 3)
CONDITIONS
EXTV
CC
= 0V
EXTV
CC
= 7.5V
Not Switching, V
EXTVCC
= 0
V
SHDN
= 0V
I
INTVCC
= 20mA, V
EXTVCC
Rising
l
l
l
MIN
5.5
2.8
TYP
MAX
80
80
UNITS
V
V
mA
µA
V
V
2.65
0
6.15
6.4
0.18
4.2
1
6.6
Maximum Current Draw from INTV
CC
and LDO33
Pins Combined. Regulated from V
IN
or EXTV
CC
(12V)
l
INTV
CC
= 5.25V
l
INTV
CC
= 4.5V
Regulated from V
IN
, I
INTVCC
= 20mA
Regulated from EXTV
CC
(12V), I
INTVCC
= 20mA
I
INTVCC
= 0mA to 50mA
INTV
CC
Falling, GATEV
CC
Connected to INTV
CC
GATEV
CC
Connected to INTV
CC
V
IN
-V
INTVCC
, I
INTVCC
= 20mA
5mA from LDO33 Pin
I
LDO33
= 0.1mA to 5mA
l
l
l
l
l
90
28
6.15
6.15
4.45
127
42
6.35
6.35
–0.5
4.65
160
245
165
55
6.55
6.55
–1.5
4.85
mA
mA
V
V
%
V
mV
mV
INTV
CC
Voltage
INTV
CC
Load Regulation
INTV
CC
, GATEV
CC
Undervoltage Lockout
INTV
CC
, GATEV
CC
Undervoltage Lockout Hysteresis
INTV
CC
Regulator Dropout Voltage
LDO33 Pin Voltage
LDO33 Pin Load Regulation
LDO33 Pin Current Limit
LDO33 Pin Undervoltage Lockout
LDO33 Pin Undervoltage Lockout Hysteresis
Switching Regulator Control
Maximum Current Sense Threshold (V
CSP
– V
CSN
)
Maximum Current Sense Threshold (V
CSN
– V
CSP
)
3.23
12
2.96
3.295
–0.25
17.25
3.04
35
3.35
–1
22
3.12
V
%
mA
V
mV
LDO33 Falling
Boost Mode, Minimum M3 Switch Duty Cycle
(LT8705E, LT8705I)
(LT8705H, LT8705MP)
Buck Mode, Minimum M2 Switch Duty Cycle
(LT8705E, LT8705I)
(LT8705H, LT8705MP)
l
l
l
l
102
100
69
67
117
117
86
86
132
134
102
104
mV
mV
mV
mV
8705fe
For more information
www.linear.com/LT8705
3
LT8705
elecTrical characTerisTics
PARAMETER
Gain from V
C
to Maximum Current Sense Voltage
(V
CSP
-V
CSN
) (A5 in the Block Diagram)
SHDN
Input Voltage High
SHDN
Input Voltage High Hysteresis
SHDN
Input Voltage Low
Device Disabled, Low Quiescent Current
(LT8705E, LT8705I)
(LT8705H, LT8705MP)
V
SHDN
= 3V
V
SHDN
= 12V
l
l
l
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V,
SHDN
= 3V unless otherwise noted. (Note 3)
CONDITIONS
Boost Mode
Buck Mode
SHDN
Rising to Enable the Device
l
MIN
TYP
150
–150
MAX
UNITS
mV/V
mV/V
V
mV
1.184 1.234 1.284
50
0.35
0.3
0
11
22
1
22
V
V
µA
µA
V
mV
V
SHDN
Pin Bias Current
SWEN Rising Threshold Voltage (Note 5)
SWEN Threshold Voltage Hysteresis (Note 5)
MODE Pin Forced Continuous Mode Threshold
MODE Pin Burst Mode Range
MODE Pin Discontinuous Mode Threshold
Soft-Start Charging Current
Soft-Start Discharge Current
Regulation Voltage for FBOUT
Regulation Voltage for FBIN
Line Regulation for FBOUT and FBIN Error Amp Reference
Voltage
FBOUT Pin Bias Current
FBOUT Error Amp EA4 g
m
FBOUT Error Amp EA4 Voltage Gain
FBIN Pin Bias Current
FBIN Error Amp EA3 g
m
FBIN Error Amp EA3 Voltage Gain
SRVO_FBIN Activation Threshold (Note 5)
SRVO_FBIN Activation Threshold Hysteresis (Note 5)
SRVO_FBOUT Activation Threshold (Note 5)
SRVO_FBOUT Activation Threshold Hysteresis (Note 5)
SRVO_FBIN, SRVO_FBOUT Low Voltage (Note 5)
SRVO_FBIN, SRVO_FBOUT Leakage Current (Note 5)
Regulation Voltages for IMON_IN and IMON_OUT
Line Regulation for IMON_IN and IMON_OUT Error Amp
Reference Voltage
CSPIN, CSNIN Bias Current
1.156 1.206 1.256
0.4
1.0
13
19
9.5
1.7
2.3
25
l
l
l
V
V
µA
µA
V
V
V
V
%/V
nA
µmho
V/V
nA
µmho
V/V
V
SS
= 0.5V
V
SS
= 0.5V
V
C
= 1.2V (LT8705E, LT8705I)
V
C
= 1.2V (LT8705H, LT8705MP)
V
C
= 1.2V (LT8705E, LT8705I)
V
C
= 1.2V (LT8705H, LT8705MP)
V
IN
= 12V to 80V; Not Switching
Current Out of Pin
l
l
l
l
Voltage Regulator Loops (Refer to Block Diagram to Locate Amplifiers)
1.193 1.207 1.222
1.191 1.207 1.222
1.184 1.205 1.226
1.182 1.205 1.226
0.002 0.005
15
315
220
Current Out of Pin
10
130
90
(V
FBIN
Falling) – (Regulation Voltage for FBIN),
V
FBOUT
= V
IMON_IN
= V
IMON_OUT
= 0V
V
FBOUT
= V
IMON_IN
= V
IMON_OUT
= 0V
(V
FBOUT
Rising) – (Regulation Voltage for FBOUT),
V
FBIN
= 3V, V
IMON_IN
= V
IMON_OUT
= 0V
V
FBIN
= 3V, V
IMON_IN
= 0V, V
IMON_OUT
= 0V
I = 100μA
V
SRVO_FBIN
= V
SRVO_FBOUT
= 2.5V
V
C
= 1.2V
V
IN
= 12V to 80V; Not Switching
BOOST Capacitor Charge Control Block Not Active
I
CSPIN
+ I
CSNIN
, V
CSPIN
= V
CSNIN
= 12V
l
l
56
72
33
89
mV
mV
–37
–29
15
110
0
–21
mV
mV
330
1
mV
µA
V
%/V
Current Regulation Loops (Refer to Block Diagram to Locate Amplifiers)
l
1.187 1.208 1.229
0.002 0.005
31
µA
8705fe
4
For more information
www.linear.com/LT8705
LT8705
elecTrical characTerisTics
PARAMETER
CSPIN, CSNIN Common Mode Operating Voltage Range
CSPIN, CSNIN Differential Operating Voltage Range
V
CSPIN-CSNIN
to IMON_IN Amplifier A7 g
m
V
CSPIN
– V
CSNIN
= 50mV, V
CSPIN
= 5.025V
(All Grades)
(LT8705E, LT8705I)
(LT8705H, LT8705MP)
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V,
SHDN
= 3V unless otherwise noted. (Note 2)
CONDITIONS
l
l
MIN
1.5
–100
0.95
0.94
0.93
100
1.55
TYP
MAX
80
100
UNITS
V
mV
mmho
mmho
mmho
µA
V
µmho
V/V
µA
µA
l
l
l
l
1
1
1
1.61
185
130
1.05
1.06
1.07
1.67
IMON_IN Maximum Output Current
IMON_IN Overvoltage Threshold
IMON_IN Error Amp EA2 g
m
IMON_IN Error Amp EA2 Voltage Gain
CSPOUT, CSNOUT Bias Current
BOOST Capacitor Charge Control Block Not Active
I
CSPOUT
+ I
CSNOUT
, V
CSPOUT
= V
CSNOUT
= 12V
I
CSPOUT
+ I
CSNOUT
, V
CSPOUT
= V
CSNOUT
= 1.5V
45
4
l
l
CSPOUT, CSNOUT Common Mode Operating Voltage Range
CSPOUT, CSNOUT Differential Mode Operating Voltage
Range
V
CSPOUT-CSNOUT
to IMON_OUT Amplifier A6 g
m
V
CSPOUT
– V
CSNOUT
= 50mV, V
CSPOUT
= 5.025V
(All Grades)
(LT8705E, LT8705I)
(LT8705H, LT8705MP)
V
CSPOUT
– V
CSNOUT
= 5mV, V
CSPOUT
= 5.0025V
(All Grades)
(LT8705E, LT8705I)
(LT8705H, LT8705MP)
0
–100
80
100
V
mV
l
l
0.95
0.94
0.93
0.65
0.55
0.5
100
1.55
1
1
1
1
1
1
1.61
185
130
1.05
1.085
1.095
1.35
1.6
1.65
1.67
mmho
mmho
mmho
mmho
mmho
mmho
µA
V
µmho
V/V
l
l
l
l
IMON_OUT Maximum Output Current
IMON_OUT Overvoltage Threshold
IMON_OUT Error Amp EA1 g
m
IMON_OUT Error Amp EA1 Voltage Gain
SRVO_IIN Activation Threshold (Note 5)
SRVO_IIN Activation Threshold Hysteresis (Note 5)
SRVO_IOUT Activation Threshold (Note 5)
SRVO_IOUT Activation Threshold Hysteresis (Note 5)
SRVO_IIN, SRVO_IOUT Low Voltage (Note 5)
SRVO_IIN, SRVO_IOUT Leakage Current (Note 5)
NMOS Gate Drivers
TG1, TG2 Rise Time
TG1, TG2 Fall Time
BG1, BG2 Rise Time
BG1, BG2 Fall Time
TG1 Off to BG1 On Delay
BG1 Off to TG1 On Delay
TG2 Off to BG2 On Delay
C
LOAD
= 3300pF (Note 4)
C
LOAD
= 3300pF (Note 4)
C
LOAD
= 3300pF (Note 4)
C
LOAD
= 3300pF (Note 4)
C
LOAD
= 3300pF Each Driver
C
LOAD
= 3300pF Each Driver
C
LOAD
= 3300pF Each Driver
(V
IMON_IN
Rising) – (Regulation Voltage for
IMON_IN), V
FBIN
= 3V, V
FBOUT
= 0V, V
IMON_OUT
= 0V
V
FBIN
= 3V, V
FBOUT
= 0V, V
IMON_OUT
= 0V
(V
IMON_OUT
Rising) – (Regulation Voltage for IMON_
OUT), V
FBIN
= 3V, V
FBOUT
= 0V, V
IMON_IN
= 0V
V
FBIN
= 3V, V
FBOUT
= 0V, V
IMON_IN
= 0V
I = 100μA
V
SRVO_IIN
= V
SRVO_IOUT
= 2.5V
–60
–49
22
–37
mV
mV
–62
–51
22
–39
mV
mV
l
l
110
0
20
20
20
20
100
80
100
330
1
mV
µA
ns
ns
ns
ns
ns
ns
ns
8705fe
For more information
www.linear.com/LT8705
5
查看更多>
热门器件
热门资源推荐
求各位指点 美国国家半导体开关稳压调整器技术问答精选 USB IEEEE1284.4 课程设计：基于单片机的波形发生器的设计 MFC如何将输入的数控专用代码转成数控线段？ EEWORLD大学堂----树莓派视频-蓝宙电子 microwave office 中文教程 明德扬FPGA连载课程第一阶段第二章FPGA设计流程 【T叔藏书阁】表面实装电感样本 转：推荐新人的学习方法和书籍
PIC单片机控制的遥控防盗报警器电路 红外线探测报警器 使用ESP8266从NTP服务器获取时间并在OLED显示器上显示 开关电源的基本组成及工作原理 用NE555制作定时器 RS-485基础知识:处理空闲总线条件的两种常见方法 如何构建一个触摸传感器电路 如何调制IC555振荡器 基于ICL296的大电流开关稳压器电源电路 基于TDA2003的简单低功耗汽车立体声放大器电路
器件捷径:
L0 L1 L2 L3 L4 L5 L6 L7 L8 L9 LA LB LC LD LE LF LG LH LI LJ LK LL LM LN LO LP LQ LR LS LT LU LV LW LX LY LZ M0 M1 M2 M3 M4 M5 M6 M7 M8 M9 MA MB MC MD ME MF MG MH MI MJ MK ML MM MN MO MP MQ MR MS MT MU MV MW MX MY MZ N0 N1 N2 N3 N4 N5 N6 N7 N8 NA NB NC ND NE NF NG NH NI NJ NK NL NM NN NO NP NQ NR NS NT NU NV NX NZ O0 O1 O2 O3 OA OB OC OD OE OF OG OH OI OJ OK OL OM ON OP OQ OR OS OT OV OX OY OZ P0 P1 P2 P3 P4 P5 P6 P7 P8 P9 PA PB PC PD PE PF PG PH PI PJ PK PL PM PN PO PP PQ PR PS PT PU PV PW PX PY PZ Q1 Q2 Q3 Q4 Q5 Q6 Q8 Q9 QA QB QC QE QF QG QH QK QL QM QP QR QS QT QV QW QX QY R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 RA RB RC RD RE RF RG RH RI RJ RK RL RM RN RO RP RQ RR RS RT RU RV RW RX RY RZ
需要登录后才可以下载。
登录取消