收藏本站
IRU3065(PbF)
APPLICATION INFORMATION
Introduction
The IRU3065 is a controller intended for an inverting
regulator solution. For example, to generate –5V from
a 5V supply. The controller is simple and only has a
voltage comparator, current hysteretic comparator, flip-
flop and MOSFET driver. It controls a typical buck boost
converter configured by a P-channel MOSFET, an in-
ductor, a diode and an output capacitor. The sensed
inductor current by a sensing resistor compares with
current comparator. The current comparator uses hys-
teresis to control the turn-on and turn-off of the transis-
tor based upon the inductor current and gated by the
When the output current is below a critical current I OCP ,
the output voltage is regulated at the desired value and
the switching frequency increases as output current
increases. At current I OCP , the switching frequency
reaches its maximum f S(MAX) . In this region, the opera-
tion is in regulation mode. When the current goes above
I OCP , the operation goes into power limit mode. The out-
put voltage starts to decrease and the output power is
limited. The switching frequency is also reduced.
Analysis shows that the current I OCP is determined by:
I OCP = 1 ×
V IN
V IN -V OUT(NOM) +V D
output voltage level. When the inductor current rises
past the hysteresis set point, the output of the current
comparator goes high. The flip-flop is reset and the P-
VI SEN(TH)
2 Rs
×
--(1)
channel MOSFET is turned off. In the mean time, the
current sense reference is reduced to near zero, giving
a zero reference threshold voltage level. As the induc-
tor current passes below this threshold, which indicates
that the inductor ’s stored energy has been transferred
to the output capacitor, the current comparator output
goes high and turns on the output transistor (if the out-
put voltage is low). By means of hysteresis, the induc-
tor charges and discharges and functions as self oscil-
Where:
Rs = Current Sensing Resistance
VI SEN(TH) = Upper Threshold Voltage at the current
comparator (when Vcc=5V, VI SEN(TH) =0.145V)
V IN = Input Voltage
V D = Diode Forward Voltage
V OUT(NOM) = Nominal Output Voltage
The maximum switching frequency is determined by:
lating. The voltage feedback comparator acts as a de-
mand governor to maintain the output voltage at the de-
sired level.
f S(MAX) =
V IN × (V D -V OUT(NOM) )
(V IN +V D -V OUT(NOM ) × L × I PEAK
By hysteresis control, the maximum switch current (also
equals inductor current) is limited by the internal cur-
f S(MAX) =
V IN × (V D -V OUT(NOM) ) × R S
VI SEN(TH) × (V IN +V D -V OUT(NOM) ) × L
---(2)
rent sensing reference. The power limit is automatically
achieved. The switching frequency is determined by a
combination of factors including the inductance, output
load current level and peak inductor current. The theo-
Where:
I PEAK = Peak Inductor Current
I PEAK is determined by:
retical output voltage and switching frequency versus
output current is shown in Figure 3.
I PEAK =
VI SEN(TH)
R S
---(3)
Output
voltage
V out
Regulation
mode
Power limit
mode
I out
The detailed operation can be seen in the theoretical
operation section
f s max
Switching
frequency
f s
I out
I ocp
Figure 3 - Theoretical output voltage and switching
frequency vs. output current.
4
www.irf.com
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
R1D-0509/H-R CONV DC/DC 1W 05VIN +/-09VOUT
AS4PG-M3/87A DIODE STD 4A 400V SMPC
RS3-4815D/H2 CONV DC/DC 3W 36-72VIN +/-15VOUT
MAX6162BESA+ IC VREF SERIES PREC 2.048V 8SOIC
GBM30DCTH-S288 CONN EDGECARD 60POS .156 EXTEND
ECM08DRSH-S288 CONN EDGECARD 16POS .156 EXTEND
GEM12DTKI CONN EDGECARD 24POS DIP .156 SLD
ECM08DRSD-S288 CONN EDGECARD 16POS .156 EXTEND
相关代理商/技术参数
IRDC3073 功能描述:PWM CONTROLLER DESIGN KIT RoHS:否 类别:编程器，开发系统 >> 过时/停产零件编号 系列:- 标准包装:1 系列:- 类型:MCU 适用于相关产品:Freescale MC68HC908LJ/LK（80-QFP ZIF 插口） 所含物品:面板、缆线、软件、数据表和用户手册 其它名称:520-1035
IRDC3137 功能描述:KIT REFERENCE DESIGN W/IRU3137 RoHS:否 类别:编程器，开发系统 >> 过时/停产零件编号 系列:- 标准包装:1 系列:- 类型:MCU 适用于相关产品:Freescale MC68HC908LJ/LK（80-QFP ZIF 插口） 所含物品:面板、缆线、软件、数据表和用户手册 其它名称:520-1035
IRDC3138 制造商:Vishay Intertechnologies 功能描述:IRU3138, SYNCHRONOUS BUCK REGULATOR, EVAL BOARD, Silicon Manufacturer:Vishay, Si
IRDC3138EVAL 制造商:IRF 制造商全称:International Rectifier 功能描述:EVALUATION BOARD USER GUIDE
IRDC3146 功能描述:KIT REFERENCE DESIGN W/IRU3146 RoHS:否 类别:编程器，开发系统 >> 过时/停产零件编号 系列:- 标准包装:1 系列:- 类型:MCU 适用于相关产品:Freescale MC68HC908LJ/LK（80-QFP ZIF 插口） 所含物品:面板、缆线、软件、数据表和用户手册 其它名称:520-1035
IRDC3146EVAL 制造商:IRF 制造商全称:International Rectifier 功能描述:IRU3146 EVALUATION BOARD USER GUIDE
IRDC3473 功能描述:电源管理IC开发工具 9999V 999A POL IC RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
IRDC3475 功能描述:电源管理IC开发工具 9999V 999A POL IC RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V