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参数资料
| 型号： | MAX17019ATM+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 18/25页 |
| 文件大小： | 0K |
| 描述： | IC VOLT CTRL QUAD OUT 48-TQFN-EP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 应用： | 嵌入式系统，控制台/机顶盒 |
| 电源电压： | 5.5 V ~ 38 V |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 48-WFQFN 裸露焊盘 |
| 供应商设备封装： | 48-TQFN-EP（6x6） |
| 包装： | 带卷 (TR) |
High-Input-Voltage Quad-Output Controller
Table 1. FREQ Table
REG A AND REG C
REG B
PIN
SELECT
LDO5
REF
GND
SYNC
SWITCHING
FREQUENCY
f SWA AND f SWC
250kHz
375kHz
500kHz
0.5 x f SYNC
SOFT-START TIME
REG A: 1200/f SWA
REG C: 900/f SWC
REG A: 4.8ms
REG C: 3.6ms
REG A: 3.2ms
REG C: 2.4ms
REG A: 2.4ms
REG C: 1.8ms
—
STARTUP
BLANKING
TIME
1500/f SWA
6ms
4ms
3ms
—
SWITCHING
FREQUENCY
f SWB
500kHz
750kHz
1MHz
f SYNC
SOFT-START
TIME
1800/f SWB
3.6ms
2.4ms
1.8ms
—
STARTUP
BLANKING
TIME
3000/f SWB
6ms
4ms
3ms
—
Light-Load Operation Control
The MAX17019 uses a light-load pulse-skipping operat-
ing mode for all switching regulators. The switching
regulators turn off the low-side MOSFETs when the cur-
rent sense detects zero inductor current. This keeps the
inductor from discharging the output capacitors and
forces the switching regulator to skip pulses under
light-load conditions to avoid overcharging the output.
Idle-Mode Current-Sense Threshold
When pulse-skipping mode is enabled, the on-time of
the step-down controller terminates when the output
voltage exceeds the feedback threshold and when the
current-sense voltage exceeds the idle-mode current-
sense threshold. Under light-load conditions, the on-
time duration depends solely on the idle-mode
current-sense threshold. This forces the controller to
source a minimum amount of power with each cycle. To
avoid overcharging the output, another on-time cannot
begin until the output voltage drops below the feed-
back threshold. Since the zero-crossing comparator
prevents the switching regulator from sinking current,
the MAX17019 switching regulators must skip pulses.
Therefore, the controller regulates the valley of the out-
put ripple under light-load conditions.
Automatic Pulse-Skipping Crossover
In skip mode, an inherent automatic switchover to PFM
takes place at light loads. This switchover is affected by
a comparator that truncates the low-side switch on-time
at the inductor current’s zero crossing. The zero-crossing
comparator senses the inductor current during the off-
time. For regulator A, once V CSPA - V CSNA drops below
the 1mV zero-crossing current-sense threshold, the com-
parator turns off the low-side MOSFET (DLA pulled low).
For regulators B and C, once the current through the low-
side MOSFET drops below 100mA, the zero-crossing
comparator turns off the low-side MOSFET.
The minimum idle-mode current requirement causes
the threshold between pulse-skipping PFM operation
and constant PWM operation to coincide with the
boundary between continuous and discontinuous
inductor-current operation (also known as the critical
conduction point). The load-current level at which
PFM/PWM crossover occurs (I LOAD(SKIP) ) is equivalent
to half the idle-mode current threshold (see the
Electrical Characteristics table for the idle-mode thresh-
olds of each regulator). The switching waveforms can
appear noisy and asynchronous when light loading
causes pulse-skipping operation, but this is a normal
operating condition that results in high light-load effi-
ciency. Trade-offs in PFM noise vs. light-load efficiency
are made by varying the inductor value. Generally, low
inductor values produce a broader efficiency vs. load
curve, while higher values result in higher full-load effi-
ciency (assuming that the coil resistance remains fixed)
and less output voltage ripple. Penalties for using high-
er inductor values include larger physical size and
degraded load-transient response (especially at low
input-voltage levels).
18
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相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX17019EVKIT+ | 功能描述:电源管理IC开发工具 Maxim Evaluation 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 |
| MAX17019NEVKIT+ | 功能描述:电源管理IC开发工具 Maxim Evaluation 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 |
| 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+ | 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 |
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