参数资料
型号: MAX1701EEE
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: 稳压器
英文描述: 18-Bit Universal Bus Transceivers With 3-State Outputs 56-SSOP -40 to 85
中文描述: 1.8 A SWITCHING REGULATOR, 340 kHz SWITCHING FREQ-MAX, PDSO16
封装: 0.150 INCH, 0.025 INCH PITCH, QSOP-16
文件页数: 15/16页
文件大小: 248K
代理商: MAX1701EEE
low-noise power for DSP, control, and RF circuitry.
Typically, RF phones spend most of their life in standby
mode with only short periods in transmit/receive mode.
During standby, maximize battery life by setting
CLK/SEL = 0; this places the IC in low-power mode (for
the lowest quiescent power consumption).
Designing a PC Board
High switching frequencies and large peak currents
make PC board layout an important part of design.
Poor design can cause excessive EMI and ground-
bounce, both of which can cause instability or regula-
tion errors by corrupting the voltage and current
feedback signals.
Power components (such as the inductor, converter IC,
filter capacitors, and output diode) should be placed as
close together as possible, and their traces should be
kept short, direct, and wide. A separate low-noise
ground plane containing the reference and signal
grounds should only connect to the power-ground
plane at one point. This minimizes the effect of power-
ground currents on the part. Consult the MAX1701 EV
kit manual for a layout example.
On multilayer boards, do not connect the ground pins
of the power components using vias through an internal
ground plane. Instead, place them close together and
route them in a star-ground configuration using compo-
nent-side copper. Then use vias to connect the star
ground to the internal ground plane.
Keep the voltage feedback network very close to the
IC, within 0.2in. (5mm) of the FB pins. Keep noisy
traces, such as from the LX pin, away from the voltage
feedback networks. Separate them with grounded
copper. Consult the MAX1700 evaluation kit for a full
PC board example.
S oft-S tart
To implement soft-start, set CLK/SEL low on power-up;
this forces low-power operation and reduces the peak
switching current to 550mA max. Once the circuit is in
regulation and start-up transients have settled,
CLK/SEL can be set high for full-power operation.
Intermittent S upply/Battery Connec tions
When boosting an input supply connected with a
mechanical switch, or a battery connected with spring
contacts, input power may sometimes be intermittent
as a result of contact bounce. When operating in PFM
mode with input voltages greater than 2.5V, restarting
after such dropouts may initiate high current pulses that
interfere with the MAX1700/MAX1701 internal MOSFET
switch control. If contact or switch bounce is anticipat-
ed in the design, use one of the following solutions.
1) Connect a capacitor (C
ONB
) from
ONB
to V
IN
, a 1M
resistor (R
ONB
) from
ONB
to GND, and tie ONA to GND
(Figure 12). This RC network differentiates fast input
edges at V
IN
and momentarily holds the IC off until V
IN
settles. The appropriate value of C
ONB
is 10
-5
times the
total output filter capacitance (C
OUT
), so a C
OUT
of
200μF results in C
ONB
= 2nF.
2) Use the system microcontroller to hold the
MAX1700/MAX1701 in shut down from the time when
power is applied (or reapplied) until the output capaci-
tance (C
OUT
) has charged to at least the input voltage.
Power-on reset times of tens of milliseconds accom-
plish this.
3) Ensure that the IC operates, or at least powers up, in
PWM mode (CLK/SEL = high). Activate PFM mode only
after the V
OUT
has settled and all of the system’s power-
on reset flags are cleared.
M
1-Cell to 3-Cell, High-Power (1A),
Low-Noise, S tep-Up DC-DC Converters
______________________________________________________________________________________
15
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
LBP
LBO
POUT
OUT
LX
PGND
FB
AIN
AO
MAX1701
QSOP
LBN
REF
POK
CLK/SEL
GND
ONB
ONA
TOP VIEW
Pin Configurations (c ontinued)
Figure 12. Connecting C
ONB
and R
ONB
when Switch or
Battery-Contact Bounce Is Anticipated
POUT
OUT
LX
13
14
15
8
7
C
OUT
200
μ
F
C
2nF
R
ONB
ONA
ONB
MAX1700
MAX1701
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相关代理商/技术参数
参数描述
MAX1701EEE+ 功能描述:直流/直流开关转换器 1-3 Cell 1A Step-Up DC/DC Converters 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
MAX1701EEE+T 功能描述:直流/直流开关转换器 1-3 Cell 1A Step-Up DC/DC Converters 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
MAX1701EEE-T 功能描述:直流/直流开关转换器 1-3 Cell 1A Step-Up DC/DC Converters 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
MAX1701EVKIT 功能描述:直流/直流开关转换器 Evaluation Kit for the MAX1700 MAX1701 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
MAX17020ETJ+ 功能描述:电压模式 PWM 控制器 Quick-PWM Step-Down Controller RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel