参数资料
型号: LTC3891EFE#TRPBF
厂商: Linear Technology
文件页数: 1/32页
文件大小: 0K
描述: IC REG CTRLR BUCK PWM CM 20TSSOP
标准包装: 2,500
PWM 型: 电流模式
输出数: 1
频率 - 最大: 835kHz
占空比: 99%
电源电压: 4 V ~ 60 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: -40°C ~ 125°C
封装/外壳: 20-TSSOP(0.173",4.40mm 宽)裸露焊盘
包装: 带卷 (TR)

LTC3891
Low I Q , 60V Synchronous
Step-Down Controller
Wide V IN Range: 4V to 60V (65V Abs Max)
Low Operating I Q : 50μA
Wide Output Voltage Range: 0.8V ≤ V OUT ≤ 24V
R SENSE or DCR Current Sensing
Phase-Lockable Frequency (75kHz to 750kHz)
Programmable Fixed Frequency (50kHz to 900kHz)
Selectable Continuous, Pulse-Skipping or Low Ripple
Selectable Current Limit
Very Low Dropout Operation: 99% Duty Cycle
Adjustable Output Voltage Soft-Start or Tracking
Power Good Output Voltage Monitor
Output Overvoltage Protection
Low Shutdown I Q : < 14μA
Internal LDO Powers Gate Drive from V IN or EXTV CC
No Current Foldback During Start-Up
Small 20-Pin 3mm × 4mm QFN and TSSOP Packages
FEATURES
n
n
n
n
n
n
n
Burst Mode ? Operation at Light Load
n
n
n
n
n
n
n
n
n
APPLICATIONS
DESCRIPTION
The LTC ? 3891 is a high performance step-down switching
regulator DC/DC controller that drives an all N-channel
synchronous power MOSFET stage. A constant fre-
quency current mode architecture allows a phase-lockable
frequency of up to 750kHz.
The 50μA no-load quiescent current extends operating run
time in battery-powered systems. OPTI-LOOP ? compensa-
tion allows the transient response to be optimized over
a wide range of output capacitance and ESR values. The
LTC3891 features a precision 0.8V reference and power
good output indicator. A wide 4V to 60V input supply range
encompasses a wide range of intermediate bus voltages
and battery chemistries. The output voltage of the LTC3891
can be programmed between 0.8V to 24V.
The TRACK/SS pin ramps the output voltages during
start-up. Current foldback limits MOSFET heat dissipation
during short-circuit conditions. The PLLIN/MODE pin se-
lects among Burst Mode operation, pulse-skipping mode,
or continuous conduction mode at light loads.
n
n
n
Automotive Always-On Systems
Battery Powered Digital Devices
Distributed DC Power Systems
L , LT, LTC, LTM, OPTI-LOOP, Burst Mode, Linear Technology and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners. Patents, including 5481178, 5705919, 6611131, 6498466, 6580258,
7230497.
TYPICAL APPLICATION
High Efficiency 3.3V Step-Down Converter
Efficiency and Power Loss vs
Output Current
V IN = 12V
V IN
4V TO 60V
22μF
V IN
LTC3891
INTV CC
2.2μF
100
90 V OUT = 3.3V
80
10000
1000
70
41.2k
2200pF
100pF
10k
FREQ
ITH
TG
BOOST
SW
BG
0.1μF
4.7μH
8m
150μF
V OUT
3.3V
5A
60
50
40
30
100
10
0.1μF
20
1
SENSE
TRACK/SS
+
10
SGND
SENSE –
V FB
PGOOD
100k
INTV CC
100k
31.6k
0
0.0001
0.001 0.01 0.1 1
OUTPUT CURRENT (A)
0.1
10
3891 TA01b
3891 TA01a
3891fa
1
相关PDF资料
PDF描述
VI-2WF-EY-F1 CONVERTER MOD DC/DC 72V 50W
VE-B5J-EV-F4 CONVERTER MOD DC/DC 36V 150W
VE-B5J-EV-F3 CONVERTER MOD DC/DC 36V 150W
LTC3856IUH#TRPBF IC REG CTRLR BUCK PWM CM 38-QFN
VI-2WD-EY-F4 CONVERTER MOD DC/DC 85V 50W
相关代理商/技术参数
参数描述
LTC3891EUDC#PBF 功能描述:IC REG CTRLR BUCK PWM CM 20-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 特色产品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 标准包装:1 系列:PowerWise® PWM 型:电压模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.5 V ~ 18 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-5°C ~ 125°C 封装/外壳:32-WFQFN 裸露焊盘 包装:Digi-Reel® 产品目录页面:1303 (CN2011-ZH PDF) 其它名称:LM3754SQDKR
LTC3891EUDC#PBF 制造商:Linear Technology 功能描述:IC DC-DC CONV 900kHz QFN20
LTC3891EUDC#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 20-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR)
LTC3891HFE#PBF 功能描述:IC REG CTRLR BUCK PWM CM 20TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX
LTC3891HFE#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 20TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX