参数资料
型号: TPS51427ARHBRG4
厂商: TEXAS INSTRUMENTS INC
元件分类: 稳压器
英文描述: DUAL SWITCHING CONTROLLER, PQCC32
封装: 5 X 5 MM, GREEN, PLASTIC, QFN-32
文件页数: 28/42页
文件大小: 2131K
代理商: TPS51427ARHBRG4
Current Limit Design Considerations
( )
(
)
OCLx
DS on max
MIN OCLvalley
V
R
I
=
(9)
OCLx
TRIP
V
5 mV
R
10
I
+
=
÷
è
(10)
TRIPx
TRIP
OCLx
V
I
R
=
(11)
(
)
(
)
(
)
TRIPx(max)
TRIP
OCLx
J
V
I
R
1
TOL
1
2900ppm / C
T
25 C
=
+
°
-
°
(12)
Shutdown and Standby Control Logic
SLUS843B – MAY 2008 – REVISED SEPTEMBER 2008 .................................................................................................................................................. www.ti.com
The current limit of Channel1 can be set using the TRIP1 pin via an external small resistor to GND. Channel2
current limit can be set via the TRIP2 pin. The sourcing current for both Channel1 and Channel2 is 5
A at room
temperature with 2900 ppm/°C built-in temperature coefficient (to compensate for the temperature dependency of
the RDS(on) of the low-side MOSFET). To take advantage of this feature, a good thermal coupling between the
TPS51427A and the low-side MOSFET has to be obtained.
The current limit adjustment range (VTRIPx) is between 0.2 V and 2 V. If 5 V is applied to the pin (TRIP1 and/or
TRIP2) directly (VTRIPx > 3.1 V), TPS51427A assumes a default of a 100-mV current limit without temperature
compensation.
Once the minimum OCL level is determined, translate the minimum OCL point (DC) into minimum valley current
by subtracting of the peak-to-peak inductor current. Then convert the current information into the voltage level for
the TPS51427A to process.
where
the low-side MOSFET at T
J = 25°C
The external resistor can be set using Equation 10.
where
I
TRIP = 5 A and the tolerance is ±5%
Once ROCLx is obtained, calculate the maximum VTRIPx voltage to make sure the maximum voltage on the TRIP1
pin and/or the TRIP2 pin is less than 3.1 V for the entire operating temperature range.
The TRIPx voltage (VTRIPx ) can be calculated by Equation 11.
And maximum VTRIPx voltage can be calculated by Equation 12.
where
I
TRIP = 5 A
TOL = 5%
T
J is assumed to be 125°C for the worst case junction temperature
Shutdown and Standby Control Logic Table
ENLDO
LDO
VREF2
VREF3
EN1
EN2
Channel1
Low
Off
Low
Off
High
On
Low
Off
High
On
High
On
High
On
High
Low
On
Off
On (if VIN > 2.2 V)
High
On
Low
High
Off
On
Off (if VIN < 2 V)
On (after Channel1
High
On
High
On
is up)
On (after Channel2
High
On
High
On
is up)
34
Copyright 2008, Texas Instruments Incorporated
Product Folder Link(s): TPS51427A
相关PDF资料
PDF描述
TC151B3327EOA713 0.25 A SWITCHING REGULATOR, 50 kHz SWITCHING FREQ-MAX, PDSO8
TC151B3530EOA723 0.25 A SWITCHING REGULATOR, 50 kHz SWITCHING FREQ-MAX, PDSO8
TC151A2333EOA723 0.25 A SWITCHING REGULATOR, 50 kHz SWITCHING FREQ-MAX, PDSO8
TC151A1645EOA713 0.25 A SWITCHING REGULATOR, 50 kHz SWITCHING FREQ-MAX, PDSO8
TC161B4113EOA713 0.25 A SWITCHING REGULATOR, 100 kHz SWITCHING FREQ-MAX, PDSO8
相关代理商/技术参数
参数描述
TPS51427ARHBT 功能描述:DC/DC 开关控制器 Dual D-Cap Sync Step Down Cntrlr RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK
TPS51427ARHBTG4 功能描述:DC/DC 开关控制器 Dual D-Cap Synch Step Down Cntrlr RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK
TPS51427RHBR 功能描述:DC/DC 开关控制器 Dual D-Cap Synch Step Down Cntrlr RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK
TPS51427RHBRG4 功能描述:DC/DC 开关控制器 Dual D-Cap Sync Step Down Cntrlr RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK
TPS51427RHBT 功能描述:DC/DC 开关控制器 Dual D-Cap Synch Step Down Cntrlr RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK