参数资料
型号: MAX1796EUA+T
厂商: Maxim Integrated Products
文件页数: 10/13页
文件大小: 0K
描述: IC REG BOOST SYNC FIX/ADJ 8UMAX
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 2,500
类型: 升压(升压)
输出类型: 两者兼有
输出数: 1
输出电压: 3.3V,5V,可调
输入电压: 1 V ~ 5.5 V
PWM 型: 电流模式
频率 - 开关: 500kHz
电流 - 输出: 300mA
同步整流器:
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 8-TSSOP,8-MSOP(0.118",3.00mm 宽)
包装: 带卷 (TR)
供应商设备封装: 8-uMAX
Low Supply Current, Step-Up DC-DC Converters
with True-Shutdown
V IN
pate this energy, minimizing the ringing at LX.
Damping LX ringing does not reduce V OUT ripple, but
does reduce EMI (Figures 3, 4, and 5).
Setting the Output Voltage
MAX1795
MAX1796
MAX1797
BATT
R1
200 ?
DAMPING
22 μ H
V OUT can be set to 3.3V or 5.0V by connecting the FB
pin to GND (5V) or OUT (3.3V). To adjust the output
voltage, connect a resistive voltage-divider from OUT to
FB to GND (Figure 6). Choose a value less than 250k ?
for R2.
SWITCH
LX
OUT
V OUT
47 μ F
BATT
47 μ F
LX
V IN
Figure 3. Simplified Diagram of Inductor Damping Switch
R3
LBI
OUT
SHDN
1M
OUTPUT
2V TO 5.5V
47 μ F
R4
MAX1795
MAX1796
R1
MAX1797
GND
LBO
FB
LOW-BATTERY
OUTPUT
R2
V LX
1V/div
2 μ s/div
Figure 4. LX Ringing for Conventional Step-Up Converter
(without Damping Switch)
V LX
1V/div
2 μ s/div
Figure 5. LX Waveform with Damping Switch
Figure 6. Setting an Adjustable Output
Use the following equation to calculate R1:
R1 = R2 [(V OUT / V FB ) - 1]
where V FB = +1.245V, and V OUT may range from +2V
to +5.5V.
Low-Battery Detection
The MAX1795/MAX1796/MAX1797 each contain an on-
chip comparator for low-battery detection. If the voltage
at LBI is above 0.85V, LBO (an open-drain output)
sinks current to GND. If the voltage at LBI is below
0.85V, LBO goes high impedance. The LBI/LBO func-
tion remains active even when the part is in shutdown.
Connect a resistive voltage-divider to LBI from BATT to
GND. The low-battery monitor threshold is set by two
resistors, R3 and R4 (Figure 6). Since the LBI bias cur-
rent is typically 2nA, large resistor values (R4 up to
250k ? ) can be used to minimize loading of the input
supply.
Calculate R3 using the following equation:
R3 = R4[(V TRIP / 0.85V) - 1]
10
______________________________________________________________________________________
相关PDF资料
PDF描述
MAX5035CUPA+ IC REG BUCK 12V 1A 8DIP
RCM28DSEN CONN EDGECARD 56POS .156 EYELET
SC104B-100 INDUCTOR SMD 10UH 2.38A 2.52MHZ
VE-2TV-EX-F1 CONVERTER MOD DC/DC 5.8V 75W
VE-20X-EX-F2 CONVERTER MOD DC/DC 5.2V 75W
相关代理商/技术参数
参数描述
MAX1797EUA 功能描述:直流/直流开关转换器 Low-Supply Current Step-Up DC/DC Conv RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
MAX1797EUA+ 功能描述:直流/直流开关转换器 Low-Supply Current Step-Up DC/DC Conv RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
MAX1797EUA+ 制造商:Maxim Integrated Products 功能描述:IC STEP-UP DC/DC CONVERTER MAX-8
MAX1797EUA+T 功能描述:直流/直流开关转换器 Low-Supply Current Step-Up DC/DC Conv RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
MAX1797EUA-T 功能描述:直流/直流开关转换器 Low-Supply Current Step-Up DC/DC Conv RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT