参数资料
型号: MAX1534ETE+
厂商: Maxim Integrated Products
文件页数: 9/16页
文件大小: 0K
描述: IC PWR SUPPLY CONTROLLER 16TQFN
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 75
应用: 电源控制器
输入电压: 4.5 V ~ 26 V
电流 - 电源: 15µA
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 16-WQFN 裸露焊盘
供应商设备封装: 16-TQFN-EP(4x4)
包装: 管件
High-Efficiency, Triple-Output, Keep-Alive
Power Supply for Notebook Computers
V IN = +7V TO +24V
10 μ F
SHDN
IN
0.01 μ F
POK
BP
LX
D1
L1
V OUT3 = +5V ALWAYS
C OUT3
100k ?
PRESET
ILIM
FB1
FB2
MAX1534
FB3
V OUT1 = +3.3V ALWAYS
V OUT2 = +1.8V ALWAYS
OUT1
LDOIN
V OUT3 = +5V ALWAYS
2.2 μ F
2.2 μ F
OUT2
GND
2.2 μ F
NOTE: SEE TABLE 1 FOR RECOMMENDED COMPONENT VALUES. SEE TABLE 2 FOR COMPONENT SUPPLIERS.
Figure 1. MAX1534 Typical Application Circuit
The MAX1534 PFM step-down topology consumes less
power than the traditional linear regulator solution when
converting from a high-input voltage source.
Buck Converter
Current-Limited Control Architecture
The MAX1534 ’ s buck converter uses a proprietary cur-
rent-limited control scheme with operation to 100% duty
cycle. This DC-to-DC converter pulses as needed to
maintain regulation, resulting in a variable switching fre-
quency that increases with the load. This eliminates the
high supply currents associated with conventional con-
stant-frequency pulse-width-modulation (PWM) con-
trollers that switch the MOSFET unnecessarily.
When the output voltage is too low, the error comparator
sets a flip-flop, which turns on the internal P-channel
MOSFET and begins a switching cycle (Figure 2). As
shown in Figure 3, the inductor current ramps up linearly,
storing energy in a magnetic field while charging the out-
put capacitor and servicing the load. The MOSFET turns
off when the peak current limit is reached, or when the
maximum on-time of 10μs is exceeded and the output
voltage is in regulation. If the output is out of regulation
and the peak current is never reached, the MOSFET
remains on, allowing a duty cycle up to 100%. This fea-
ture ensures the lowest possible dropout voltage. Once
the MOSFET turns off, the flip-flop resets, the inductor
current is pulled through D1, and the current through the
inductor ramps back down, transferring the stored ener-
gy to the output capacitor and load. The MOSFET
remains off until the 0.42μs minimum off-time expires,
and the output voltage drops out of regulation.
Current Limit (ILIM)
The MAX1534 ’ s buck converter has an adjustable peak
current limit. Configure this peak current limit by con-
necting ILIM as shown in Table 3. Choose a current
limit that realistically reflects the maximum load current.
The maximum output current is half the peak current
limit. Although choosing a lower current limit allows
using an inductor with a lower current rating, it requires
a higher inductance (see Inductor Selection ) and does
little to reduce inductor package size.
ILIM can be dynamically switched to achieve the high-
est efficiency over the load range. (See Buck Efficiency
vs. Load Current (Circuit 1) in the Typical Operating
Characteristics .
Linear Regulators
Internal P-Channel Pass Transistor
The MAX1534 features two 1.5 ? P-channel MOSFET
pass transistors. A P-channel MOSFET provides sever-
al advantages over similar designs using PNP pass
transistors, including longer battery life. It requires no
_______________________________________________________________________________________
9
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MAX1534ETE+ 功能描述:电流和电力监控器、调节器 PS Controllers for for Notebooks RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX1534ETE+T 功能描述:电流和电力监控器、调节器 PS Controllers for for Notebooks RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX1534ETE-T 功能描述:电流和电力监控器、调节器 RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX1535AETJ 功能描述:电池管理 RoHS:否 制造商:Texas Instruments 电池类型:Li-Ion 输出电压:5 V 输出电流:4.5 A 工作电源电压:3.9 V to 17 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:VQFN-24 封装:Reel
MAX1535AETJ+T 功能描述:电池管理 RoHS:否 制造商:Texas Instruments 电池类型:Li-Ion 输出电压:5 V 输出电流:4.5 A 工作电源电压:3.9 V to 17 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:VQFN-24 封装:Reel