目录mi1嘉泰姆

1.产品概述                       2.产品特点mi1嘉泰姆
3.应用范围                       4.下载产品资料PDF文档 mi1嘉泰姆
5.产品封装图                     6.电路原理图                   mi1嘉泰姆
7.功能概述                        8.相关产品mi1嘉泰姆

一,产品概述(General Description)         mi1嘉泰姆

 The CXSD6299 is a voltage mode, fixed 300kHz-switch-ing frequency,mi1嘉泰姆
and synchronous buck controller. The CXSD6299 allows wide input voltagemi1嘉泰姆
that is either a single 5~12V or two supply voltage(s) for various applications.mi1嘉泰姆
A power-on-reset (POR) circuit monitors the VCC supply voltage to preventmi1嘉泰姆
wrong logic controls. A built-in digital soft-start circuit prevents the outputmi1嘉泰姆
voltages from over-shoot as well as limits the input current. An internal 0.8Vmi1嘉泰姆

temperature-compensated reference voltage with high accuracy is designed to mi1嘉泰姆

meet the requirement of low out-put voltage applications. The CXSD6299 mi1嘉泰姆

provides excel-lent output voltage regulations against load current variation.mi1嘉泰姆

 The controller’s over-current protection monitors the out-put current bymi1嘉泰姆
using the voltage drops across the RDS(ON)of low-side MOSFET, eliminatingmi1嘉泰姆
the need for a current sensing resistor that features high efficiency and low cost.mi1嘉泰姆

The CXSD6299 also integrates over-voltage protection (OVP) and under-voltage mi1嘉泰姆

protection circuit which moni-tors the FB voltage to prevent the PWM output mi1嘉泰姆

from over and under voltage.mi1嘉泰姆

  The CXSD6299 is available in a simple SOP-8P packagemi1嘉泰姆
二.产品特点(Features)mi1嘉泰姆

1.)Wide Operation Supply Voltage from 5V to 12Vmi1嘉泰姆
2.)Power-On-Reset Monitoring on VCCmi1嘉泰姆
3.)Excellent Reference Voltage Regulationsmi1嘉泰姆
     - 0.8V Internal Referencemi1嘉泰姆
     - ±1% Over-Temperature Rangemi1嘉泰姆
4.)Integrated Soft-Startmi1嘉泰姆
5.)Automatic PSM/PWM Modesmi1嘉泰姆
6.)Voltage Mode PWM Operation with 90% (Max.)Duty Cyclemi1嘉泰姆
7.)Under-Voltage Protectionmi1嘉泰姆
8.)Adjustable Over-Current Protection Thresholdmi1嘉泰姆
- Sensing the RDS(ON) of Low-Side MOSFETmi1嘉泰姆
9.)Over-Voltage Protection Under-Voltage Protectionmi1嘉泰姆
     Simple SOP-8P Packagemi1嘉泰姆
10.)Lead Free and Green Devices Available (RoHS Compliant)mi1嘉泰姆
三,应用范围 (Applications)mi1嘉泰姆

Graphic Cardsmi1嘉泰姆
DSL, Switch HUBmi1嘉泰姆
Wireless Lanmi1嘉泰姆
Notebook Computermi1嘉泰姆
Mother Boardmi1嘉泰姆
LCD Monitor/TVmi1嘉泰姆
四.下载产品资料PDF文档 mi1嘉泰姆

需要详细的PDF规格书请扫一扫微信联系我们，还可以获得免费样品以及技术支持！mi1嘉泰姆

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五,产品封装图 (Package)mi1嘉泰姆

mi1嘉泰姆

六.电路原理图mi1嘉泰姆

mi1嘉泰姆
七,功能概述mi1嘉泰姆

Layout Considerationmi1嘉泰姆
In any high switching frequency converter, a correct lay-out is important to ensure proper operation of themi1嘉泰姆
regulator. With power devices switching at 300kHz,the resulting current transient will cause voltage spike acrossmi1嘉泰姆
the interconnecting impedance and parasitic circuit elements. As an example, consider the turn-off transitionmi1嘉泰姆
of the PWM MOSFET. Before turn-off, the MOSFET is car-rying the full load current. During turn-off, current stopsmi1嘉泰姆
flowing in the MOSFET and is free-wheeling by the lower MOSFET and parasitic diode. Any parasitic inductance ofmi1嘉泰姆
the circuit generates a large voltage spike during the switching interval. In general, using short and wide printedmi1嘉泰姆
circuit traces should minimize interconnecting imped-mi1嘉泰姆
Layout Consideration (Cont.)mi1嘉泰姆
ances and the magnitude of voltage spike. And signal and power grounds are to be kept separate till combinedmi1嘉泰姆
using ground plane construction or single point grounding. Figure 8. illustrates the layout, with bold linesmi1嘉泰姆
indicating high current paths; these traces must be short and wide. Components along the bold lines should bemi1嘉泰姆
placed lose together. Below is a checklist for your layout:mi1嘉泰姆
- Keep the switching nodes (UGATE, LGATE, and PHASE) away from sensitive small signal nodes since thesemi1嘉泰姆
nodes are fast moving signals. Therefore, keep traces to these nodes as short as possible.mi1嘉泰姆
The traces from the gate drivers to the MOSFETs (UG and LG) should be short and wide.mi1嘉泰姆
- Place the source of the high-side MOSFET and the drain of the low-side MOSFET as close as possible. Minimiz-mi1嘉泰姆
ing the impedance with wide layout plane between the two pads reduces the voltage bounce of the node.mi1嘉泰姆
- Decoupling capacitor, compensation component, the resistor dividers, and boot capacitors should be closemi1嘉泰姆
their pins. (For example, place the decoupling ceramic capacitor near the drain of the high-side MOSFET asmi1嘉泰姆
close as possible. The bulk capacitors are also placed near the drain).mi1嘉泰姆
- The input capacitor should be near the drain of the up-per MOSFET; the output capacitor should be near themi1嘉泰姆
loads. The input capacitor GND should be close to the output capacitor GND and the lower MOSFET GND.mi1嘉泰姆
- The drain of the MOSFETs (VIN and PHASE nodes) should be a large plane for heat sinking.mi1嘉泰姆
- The ROCSET resistance should be placed near the IC as close as possible.mi1嘉泰姆

八,相关产品                更多同类产品...... mi1嘉泰姆

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