参数资料
型号: MC34702EK
厂商: Freescale Semiconductor
文件页数: 18/39页
文件大小: 0K
描述: IC POWER SUPPLY MCU 3A 32-SOIC
标准包装: 42
应用: 电源
电流 - 电源: 60mA
电源电压: 2.8 V ~ 6 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 32-SOIC(0.295",7.50mm 宽)
供应商设备封装: 32-SOIC
包装: 管件
配用: KIT33702DWBEVB-ND - KIT FEATURES THE MC34701
FUNCTIONAL DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
INTRODUCTION
The 34702 incorporates a high-performance synchronous
buck regulator, supplying the microprocessor’s core, and a
low dropout (LDO) linear regulator providing the
microprocessor I / O and bus voltages. This device
incorporates many advanced features; e.g., precisely
maintained up / down power sequencing, ensuring the proper
operation and protection of the CPU and power system.
Bandgap
Voltage
Reference
Boost Regulator
Buck Control Logic
Buck HS and
LS Driver
Switcher
Oscillator
300 kHz
Power Sequencing
Voltage Margining
Watchdog Timer
I 2 C Interface
VDDI
Internal
Supply
Linear Regulator
Control
I LIM
UVLO
Reset Control
POR Timer
Bandgap
Voltage
Reference
Thermal Shutdown
Figure 11. 34702 Functional Internal Block Diagram
BOOST REGULATOR
A boost regulator provides a high voltage necessary to
properly drive the buck regulator power MOSFETs,
especially during the low input voltage condition. The LDO
regulator external N-channel MOSFET gate is also powered
from the boost regulator. In order to properly enhance the
high side MOSFETs when only a +3.3V supply rail powers
the integrated circuit, the boost regulator provides an output
voltage of 7.75V nominal value.
The 34702 boost regulator uses a simple hysteretic
current control technique, which allows fast power-up and
does not require any compensation. When the boost
regulator main power switch (low side) is turned on, the
current in the inductor starts to ramp up. After the inductor
current reaches the upper current limit (nominally set at
1.0A), the low side switch is turned off and the current
When the inductor current falls below the valley current limit
value (nominally 600mA), the low side switch is turned on
again, starting the next switching cycle. After the boost
regulator output capacitor reaches approximately 6.0 volts,
the peak and valley current limit levels are proportionally
scaled down to approximately one fifth of their original values.
When the boost regulator reaches its regulation limit (7.75V
typical), the low side switch is turned off until the output
voltage falls below the regulation limit again.
The higher current limit values in the beginning of the
boost regulator start-up sequence allow fast power-up of the
whole IC, while the normal operation with reduced current
limit greatly reduces the switching noise and therefore
improves the overall EMC performance. See Figure 12 for
the boost regulator output voltage and inductor current
waveforms (picture not to scale).
charges the output capacitor through the internal rectifier.
34702
Analog Integrated Circuit Device Data ?
18
Freescale Semiconductor
相关PDF资料
PDF描述
EBM31DCWS CONN EDGECARD 62POS DIP .156 SLD
VI-B5B-EW CONVERTER MOD DC/DC 95V 100W
H3AWH-3418G IDC CABLE - HSC34H/AE34G/HPL34H
H6MMH-2636M DIP CABLE - HDM26H/AE26M/HDM26H
ISL6532BCR-T IC REG/CTRLR ACPI DUAL DDR 20QFN
相关代理商/技术参数
参数描述
MC34702EKR2 功能描述:开关变换器、稳压器与控制器 QUICCSUPPLY2 RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
MC34703 制造商:SPC Multicomp 功能描述:HEADER R/ANGLE 7WAY 制造商:SPC Multicomp 功能描述:HEADER, R/ANGLE, 7WAY
MC34703PNB 功能描述:开关变换器、稳压器与控制器 QUICC SUPPLY 3 RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
MC34704AEP 功能描述:开关变换器、稳压器与控制器 DSC8 PASS.1.3 RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
MC34704AEPR2 功能描述:开关变换器、稳压器与控制器 DSC8 PASS1.3 TAPE RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel