参数资料
型号: LTC3827IG-1#PBF
厂商: Linear Technology
文件页数: 17/32页
文件大小: 0K
描述: IC REG CTRLR BUCK PWM CM 28-SSOP
标准包装: 47
系列: PolyPhase®
PWM 型: 电流模式
输出数: 2
频率 - 最大: 580kHz
占空比: 99.4%
电源电压: 4 V ~ 36 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: -40°C ~ 85°C
封装/外壳: 28-SSOP(0.209",5.30mm 宽)
包装: 管件
产品目录页面: 1336 (CN2011-ZH PDF)
LTC3827-1
APPLICATIONS INFORMATION
Tracking and Soft-Start (TRACK/SS Pins)
1/2 LTC3827-1
The start-up of each V OUT is controlled by the voltage on
C SS
TRACK/SS
the respective TRACK/SS pin. When the voltage on the
TRACK/SS pin is less than the internal 0.8V reference, the
LTC3827-1 regulates the V FB pin voltage to the voltage on
the TRACK/SS pin instead of 0.8V. The TRACK/SS pin can
be used to program an external soft-start function or to
allow V OUT to “track” another supply during start-up.
Soft-start is enabled by simply connecting a capacitor
from the TRACK/SS pin to ground, as shown in Figure 5.
An internal 1μA current source charges up the capacitor,
providing a linear ramping voltage at the TRACK/SS pin.
The LTC3827-1 will regulate the V FB pin (and hence V OUT )
according to the voltage on the TRACK/SS pin, allowing
V OUT to rise smoothly from 0V to its ?nal regulated value.
SGND
38271 F05
Figure 5. Using the TRACK/SS Pin to Program Soft-Start
V X (MASTER)
V OUT (SLAVE)
The total soft-start time will be approximately:
TIME
38271 F06A
t SS = C SS ?
0.8V
1 μ A
(6a) Coincident Tracking
Alternatively, the TRACK/SS pin can be used to track two
(or more) supplies during start-up, as shown qualitatively
in Figures 6a and 6b. To do this, a resistor divider should
be connected from the master supply (V X ) to the TRACK/
SS pin of the slave supply (V OUT ), as shown in Figure 7.
During start-up V OUT will track V X according to the ratio
set by the resistor divider:
V X (MASTER)
V OUT (SLAVE)
R + R TRACKB
V X
V OUT
=
R A
R TRACKA
? TRACKA
R A +R B
TIME 38271 F06B
(6b) Ratiometric Tracking
For coincident tracking (V OUT = V X during start-up),
R A = R TRACKA
R B = R TRACKB
INTV CC Regulators
Figure 6. Two Different Modes of Output
Voltage Tracking
V x V OUT
The LTC3827-1 features two separate internal P-channel
low dropout linear regulators (LDO) that supply power
at the INTV CC pin from either the V IN supply pin or the
EXTV CC pin, respectively, depending on the connection
of the EXTV CC pin. INTV CC powers the gate drivers and
much of the LTC3827-1’s internal circuitry. The V IN LDO
R TRACKB
R TRACKA
R B
R A
1/2 LTC3827-1
V FB
TRACK/SS
38271 F07
regulates the voltage at the INTV CC pin to 5.25V and the
Figure 7. Using the TRACK/SS Pin for Tracking
38271fe
17
相关PDF资料
PDF描述
H2BBT-10108-W4-ND JUMPER-H1500TR/A2015W/H1500TR 8"
ELL-6GM470M COIL PWR CHOKE 47UH 420MA SMD
SRP1040-6R8M INDUCTOR 6.8UH 6.5A SMD
SRP1040-5R6M INDUCTOR 5.6UH 7A SMD
LTC1148CS-3.3 IC REG CTRLR BUCK PWM CM 14-SOIC
相关代理商/技术参数
参数描述
LTC3827IUH#PBF 功能描述:IC REG CTRLR BUCK PWM CM 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 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
LTC3827IUH#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 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
LTC3828EG#PBF 功能描述:IC REG CTRLR BUCK PWM CM 28-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 标准包装:2,000 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:1MHz 占空比:50% 电源电压:9 V ~ 10 V 降压:无 升压:是 回扫:是 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:8-TSSOP(0.173",4.40mm 宽) 包装:带卷 (TR)
LTC3828EG#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 28-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 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
LTC3828EUH 制造商:Linear Technology 功能描述:DC DC Cntrlr Dual-OUT Sync Step Down 4.5V to 28V Input 32-Pin QFN EP