- 您现在的位置：买卖IC网 > PDF目录20504 > IRDC3856 (International Rectifier)BOARD EVAL FOR IR3856 PDF资料下载
参数资料
| 型号： | IRDC3856 |
| 厂商： | International Rectifier |
| 文件页数： | 12/35页 |
| 文件大小： | 0K |
| 描述： | BOARD EVAL FOR IR3856 |
| 标准包装： | 1 |
| 系列： | SupIRBuck™ |
| 主要目的： | DC/DC，步降 |
| 输出及类型： | 1，非隔离 |
| 输出电压： | 1.8V |
| 电流 - 输出： | 0 ~ 6A |
| 输入电压： | 12V |
| 稳压器拓扑结构： | 降压 |
| 频率 - 开关： | 600kHz |
| 板类型： | 完全填充 |
| 已供物品： | 板 |
| 已用 IC / 零件： | IR3856 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页当前第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页
PD-97528
IR3856MPbF
Circuit Description
THEORY OF OPERATION
Introduction
The IR3856 uses a PWM voltage mode control
scheme with external compensation to provide
good noise immunity and maximum flexibility in
selecting inductor values and capacitor types.
The switching frequency is programmable from
250kHz to 1.5MHz and provides the capability of
optimizing the design in terms of size and
performance.
IR3856 provides precisely regulated output
voltage programmed via two external resistors
from 0.7V to 0.9*Vin.
The IR3856 operates with an external bias
supply from 4.5V to 5.5V, allowing an extended
operating input voltage range from 1.5V to 21V.
The device utilizes the on-resistance of the low
side MOSFET as current sense element, this
method enhances the converter’s efficiency and
reduces cost by eliminating the need for external
current sense resistor .
IR3856 includes two low R ds(on) MOSFETs using
IR’s HEXFET technology. These are specifically
designed for high efficiency applications.
Under-Voltage Lockout and POR
The under-voltage lockout circuit monitors the
input supply Vcc and the Enable input. It assures
that the MOSFET driver outputs remain in the off
state whenever either of these two signals drop
below the set thresholds. Normal operation
resumes once Vcc and Enable rise above their
thresholds.
The POR (Power On Ready) signal is generated
when all these signals reach the valid logic level
(see system block diagram). When the POR is
asserted the soft start sequence starts (see soft
start section).
Enable
The Enable features another level of flexibility for
start up. The Enable has precise threshold which
is internally monitored by Under-Voltage Lockout
(UVLO) circuit. Therefore, the IR3856 will turn on
only when the voltage at the Enable pin exceeds
this threshold, typically, 1.2V.
Rev 4.0
If the input to the Enable pin is derived from the
bus voltage by a suitably programmed resistive
divider, it can be ensured that the IR3856 does not
turn on until the bus voltage reaches the desired
level. Only after the bus voltage reaches or
exceeds this level will the voltage at Enable pin
exceed its threshold, thus enabling the IR3856.
Therefore, in addition to being a logic input pin to
enable the IR3856, the Enable feature, with its
precise threshold, also allows the user to
implement an Under-Voltage Lockout for the bus
voltage V in . This is desirable particularly for high
output voltage applications, where we might want
the IR3856 to be disabled at least until V in
exceeds the desired output voltage level.
Fig. 3a. Normal Start up, Device turns on
when the Bus voltage reaches 10.2V
Figure 3b. shows the recommended start-up
sequence for the non-sequenced operation of
IR3856, when Enable is used as a logic input.
Fig. 3b. Recommended startup sequence,
Non-Sequenced operation
12
相关PDF资料 |
PDF描述 |
|---|---|
| IRDC3839 | KIT EVAL REG 6A SUPIRBUCK DC/DC |
| RCM06DTMH | CONN EDGECARD 12POS R/A .156 SLD |
| SBRB2545CTT4G | DIODE SCHOTTKY 45V 15A D2PAK |
| VI-23X-CX-S | CONVERTER MOD DC/DC 5.2V 75W |
| TC1427CUA | IC MOSFET DVR 1.2A DUAL HS 8MSOP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| IRDC3856 - SUPIRBUCK | 制造商:International Rectifier 功能描述:INTERNATIONAL RECIFIER - GEN 2.1 SUPIRBUCK FAMILY - Bulk |
| IRDC3856 | 制造商:International Rectifier 功能描述:; MCU Supported Families:IR3856; Feature |
| IRDC3856W | 功能描述:电源管理IC开发工具 User Guide IR3856W Eval Brd 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 |
| IRDC3859 | 功能描述:电源管理IC开发工具 User Guide IR3859 Eval Brd 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 |
| IRDC3859 - SUPIRBUCK | 制造商:International Rectifier 功能描述:INTERNATIONAL RECIFIER - GEN 2.1 SUPIRBUCK FAMILY - Bulk |
发布紧急采购，3分钟左右您将得到回复。