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参数资料
| 型号： | MAX5098AATJ+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 15/28页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK BST ADJ 1A/2A 32TQFN |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 类型： | 降压（降压），升压（升压） |
| 输出类型： | 可调式 |
| 输出数： | 2 |
| 输出电压： | 0.8 V ~ 0.85 V，4.5 V ~ 28 V |
| 输入电压： | 4.5 V ~ 19 V |
| PWM 型： | 电压模式 |
| 频率 - 开关： | 200kHz ~ 2.2MHz |
| 电流 - 输出： | 1A，2A |
| 同步整流器： | 无 |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 32-WFQFN 裸露焊盘 |
| 包装： | 带卷 (TR) |
| 供应商设备封装： | 32-TQFN-EP（5x5） |
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Dual, 2.2MHz, Automotive Buck or Boost
Converter with 80V Load-Dump Protection
Internal Oscillator/Out-of-Phase Operation
The internal oscillator generates the 180° out-of-phase
clock signal required by each regulator. The switching
frequency of each converter (f SW ) is programmable
from 200kHz to 2.2MHz using a single 1% resistor at
R OSC . See the Setting the Switching Frequency section.
With dual synchronized out-of-phase operation, the
MAX5098A’s internal MOSFETs turn on 180° out-of-
phase. The instantaneous input current peaks of both
regulators do not overlap, resulting in reduced RMS rip-
ple current and input-voltage ripple. This reduces the
required input capacitor ripple current rating, allows for
fewer or less expensive capacitors, and reduces
shielding requirements for EMI.
Synchronization (SYNC)/
Clock Output (CKO)
The main oscillator can be synchronized to the system
clock by applying an external clock (f SYNC ) at SYNC.
The f SYNC frequency must be twice the required oper-
ating frequency of an individual converter. Use a TTL
logic signal for the external clock with at least 100ns
pulse width. R OSC is still required when using external
synchronization. Program the internal oscillator fre-
quency to have f SW = 1/2 f SYNC. The device is properly
synchronized if the SYNC frequency, f SYNC , varies
within ±20%.
Two MAX5098As can be connected in the master-slave
configuration for four ripple-phase operation (Figure 1).
Output Voltage vs. Converter Switching Frequency
graph in the Typical Operating Characteristics . For
input voltage ranges higher than 5.5V, disconnect V L
from V+.
Bypass V+ to SGND with a 1μF or greater ceramic
capacitor placed close to the MAX5098A. Bypass V L
with a 4.7μF ceramic capacitor to SGND.
Undervoltage Lockout/
Soft-Start/Soft-Stop
The MAX5098A includes an undervoltage lockout with
hysteresis and a power-on-reset circuit for converter
turn-on and monotonic rise of the output voltage. The
falling UVLO threshold is internally set to 4.1V (typ) with
180mV hysteresis. Hysteresis at UVLO eliminates “chat-
tering” during startup. When V L drops below UVLO, the
internal MOSFET switches are turned off.
The MAX5098A digital soft-start reduces input inrush
currents and glitches at the input during turn-on. When
UVLO is cleared and EN_ is high, digital soft-start slow-
ly ramps up the internal reference voltage in 64 steps.
The total soft-start period is 4096 internal oscillator
switching cycles.
Driving EN_ low initiates digital soft-stop that slowly
ramps down the internal reference voltage in 64 steps.
The total soft-stop period is equal to the soft-start period.
To calculate the soft-start/soft-stop period, use the fol-
lowing equation:
The MAX5098A provides a clock output (CKO) that is
45° phase-shifted with respect to the internal switch
turn-on edge. Feed the CKO of the master to the SYNC
input of the slave. The effective input ripple switching
t SS ( ms ) =
4096
f CKO ( kHz )
frequency is four times the individual converter’s switch-
ing frequency. When driving the master converter using
an external clock at SYNC, set the f SYNC clock duty
cycle to 50% for effective 90° phase-shifted interleaved
operation. When a SYNC is applied (and FSEL_1 = 0),
converter 1 duty cycle is limited to 75% (max).
Input Voltage (V+)/
Internal Linear Regulator (V L )
All internal control circuitry operates from an internally
regulated nominal voltage of 5.2V (V L ). At higher input
voltages (V+) of 5.2V to 19V, V L is regulated to 5.2V. At
5.2V or below, the internal linear regulator operates in
dropout mode, where V L follows V+. Depending on the
load on V L , the dropout voltage can be high enough to
reduce V L below the undervoltage lockout (UVLO)
threshold. Do not use V L to power external circuitry.
For input voltages less than 5.5V, connect V+ and V L
together. The load on V L is proportional to the switching
frequency of converter 1 and converter 2. See the V L
where f CKO is the internal oscillator and f CKO is twice
each converters’ switching frequency (FSEL_1 = V L )
Enable (EN1, EN2)
The MAX5098A dual converter provides separate
enable inputs, EN1 and EN2, to individually control or
sequence the output voltages. These active-high enable
inputs are TTL compatible. Driving EN_ high initiates
soft-start of the converter, and PGOOD_ goes logic-high
when the converter output voltage reaches the
V TPGOOD_ threshold. Driving EN_ low initiates a soft-
stop of the converter, and immediately forces PGOOD_
low. Use EN1, EN2, and PGOOD1 for sequencing (see
Figure 2). Connect PGOOD1 to EN2 to make sure con-
verter 1’s output is within regulation before converter 2
starts. Add an RC network from V L to EN1 and EN2 to
delay the individual converter. Sequencing reduces
input inrush current and possible chattering. Connect
EN_ to V L for always-on operation.
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相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX5099 | 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:Dual, 2.2MHz, Automotive Synchronous Buck Converter with 80V Load-Dump Protection |
| MAX5099ATJ | 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:Dual, 2.2MHz, Automotive Synchronous Buck Converter with 80V Load-Dump Protection |
| MAX5099ATJ+ | 功能描述:直流/直流开关转换器 Dual 2.2MHz Synch Buck Converter 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 |
| MAX5099ATJ+T | 功能描述:直流/直流开关转换器 Dual 2.2MHz Synch Buck Converter 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 |
| MAX5099EVKIT+ | 功能描述:电源管理IC开发工具 MAX5098A/99 Eval Kit RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V |
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