L6738：单相降压电源转换解决方案
ST公司的L6738是集成了大电流驱动器的单相降压电源控制器,VIN输入电压可低至1.5V,电源电压从5V到12V,轻负载效率优化,集成了0.8V基准电压,输出电压精度±0.5%,主要用在存储器和终端电源,子系统电源(MCH, IOCH, PCI),CPU和DSP电源,分布式电源和通用DC/DC转换器.本文介绍了L6738主要特性,框图,典型应用电路以及评估板STEVAL-ISA075V1主要特性,电路图和材料清单.
The L6738 is a single-phase step-down controller with integrated high-current drivers that provides complete control logic and protection to realize a DC-DC converter.
The device flexibility allows the management of conversions with power input VIN as low as 1.5 V and the device supply voltage ranging from 5 V to 12 V bus.
The L6738 features a proprietary algorithm that allows light-load efficiency optimization, boosting efficiency without compromising the output voltage ripple.
The integrated 0.8 V reference allows the generation of output voltages with ±0.5% accuracy over line and temperature variations.
The oscillator is programmable up to 600 kHz. The L6738 provides a programmable dual-level overcurrent protection and overvoltage protection. The current information is monitored across the inductor DCR.
The L6738 is available in a VFQFPN 16 3x3 mm package.
L6738主要特性:
■ Flexible power supply from 5 V to 12 V bus
■ Power conversion input as low as 1.5 V
■ Light-load efficiency optimization
■ Embedded bootstrap diode
■ VIN detector
■ 0.8 V internal reference
■ 0.5% output voltage accuracy
■ Remote GND recovery
■ High-current integrated drivers
■ Sensorless and programmable precise-OC sense across inductor DCR
■ OV protection
■ Programmable oscillator up to 600 kHz
■ LS-less to manage pre-bias startup
■ Adjustable output voltage
■ Disable function
■ Internal soft-start
■ VFQFPN 16 3x3 mm package
L6738应用:
■ Memory and termination supply
■ Subsystem power supply (MCH, IOCH, PCI)
■ CPU and DSP power supply
■ Distributed power supply
■ General DC-DC converter
图1. L6738框图
图2. L6738快速保护的典型应用电路图
图3. L6738典型应用电路图
评估板STEVAL-ISA075V1
High efficiency DC-DC converter - compact solution based on L6738
The STEVAL-ISA075V1 product evaluation board is a compact solution designed for testing the performance of the L6738.
The L6738 is a single-phase step-down controller with integrated high-current drivers that provides complete control logic and protection for DC-DC converters.
评估板STEVAL-ISA075V1主要特性:
Compact size (25.4 mm x 14.6 mm)
4 layers
VIN< 6 Vhttp://www.youerw.com
VOUTup to 3.5 V
IOUTup to 8 A (depending on VOUT)
FSW= 600 KHz
Dual power MOS option (2 x STL 3x3 or 1 x Dual SO8)
CIN= 2 x GRM21BR60J226ME39 (22 uF,6.3 V, 0805)
COUT= 2 or 3 x GRM31CC70G226KE01 (22 uF, 4 V, 1206)
Dual choke options (WE 744310095 or VITEC 59Px8970)
RoHS compliant
/fanga/UploadFiles_1068/201409/20140901171049962.jpg
图4. 评估板STEVAL-ISA075V1外形图
图5. 评估板STEVAL-ISA075V1电路图
评估板STEVAL-ISA075V1材料清单: