- 您现在的位置：买卖IC网 > PDF目录1839 > MAX17083ETG+T (Maxim Integrated Products)IC REG BUCK ADJ 5A 24TQFN PDF资料下载
参数资料
| 型号： | MAX17083ETG+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 10/15页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK ADJ 5A 24TQFN |
| 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） |
| 输出类型： | 可调式 |
| 输出数： | 1 |
| 输出电压： | 0.75 V ~ 2.7 V |
| 输入电压： | 2.4 V ~ 5.5 V |
| PWM 型： | 电流模式，混合 |
| 频率 - 开关： | 500kHz |
| 电流 - 输出： | 5A |
| 同步整流器： | 无 |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 24-WFQFN 裸露焊盘 |
| 包装： | 带卷 (TR) |
| 供应商设备封装： | 24-TQFN-EP（4x4） |
Low-Voltage, Internal Switch,
Step-Down Regulator
SMPS Detailed Description
Fixed-Frequency,
Current-Mode PWM Controller
The heart of the current-mode PWM controller is a multi-
stage, open-loop comparator that compares the output
voltage-error signal with respect to the reference volt-
age, the current-sense signal, and the slope compensa-
tion ramp (Figure 2). The MAX17083 uses a direct-
summing configuration, approaching ideal cycle-to-
cycle control over the output voltage without a traditional
error amplifier and the phase shift associated with it.
Frequency Selection (FREQ)
The FREQ input selects the PWM mode switching fre-
quency. FREQ is a four-level input to set the regulator
switching frequency. The regulator’s switching frequen-
cy is set according to Table 1, and latched at the
beginning of soft-start. High-frequency (FREQ = V CC )
operation optimizes the application for the smallest
component size, trading off efficiency due to higher
switching losses. This might be acceptable in ultra-
portable devices where the load currents are lower.
Low-frequency (FREQ = GND) operation offers the best
overall efficiency at the expense of component size and
board space.
Table 1. MAX17083 FREQ Table
Adjustable Output-Voltage Operation Mode
The MAX17083 produces an adjustable 0.75V to 2.7V
output voltage from the system’s 3.3V or 5V input sup-
ply by using a resistive feedback divider. Set FB to
0.75V (SET = GND) in adjustable mode.
Light-Load Operation
An inherent automatic switchover to pulse-skipping
(PFM operation) 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. Once the cur-
rent through the low-side MOSFET drops below 100mA,
the zero-crossing comparator, turns off the low-side
MOSFET. This prevents the inductor from discharging
the output capacitors and forces the switching regula-
tor to skip pulses under light-load conditions to avoid
overcharging the output.
Idle-Mode Current-Sense Threshold
When MAX17083 operates in pulse-skipping mode, the
on-time of the step-down controller terminates when
both the output voltage exceeds the feedback thresh-
old, and 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 con-
FREQ PIN
SELECT
V CC
Open
REF
GND
SWITCHING
FREQ, f SW
1.5MHz
1MHz
750kHz
500kHz
SOFT-START
TIME (ms)
1833/f SW
1.22
1.83
2.44
3.67
STARTUP
BLANKING
TIME (ms)
3055/f SW
2.0
3.1
4.1
6.1
troller to source a minimum amount of power with each
cycle. To avoid overcharging the output, another on-
time cannot be initiated until the output voltage drops
below the feedback threshold. Since the zero-crossing
comparator prevents the switching regulator from sink-
ing current, the MAX17083 switching regulator must
skip pulses. Therefore, the controller regulates the
valley of the output ripple under light-load conditions.
The minimum idle-mode current requirement causes
the threshold between pulse-skipping PFM operation
FB Regulation Selection (SET)
The SET input selects one of the four preset feedback
regulation voltage levels. The SET pin is a four-level
input signal to set the FB regulation voltage. The regu-
lator’s feedback regulation voltage is set according to
Table 2, and latched at the beginning of soft-start.
Table 2. MAX17083 SET Table
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-
old of the regulator). The switching waveforms can
SET PIN SELECT
V CC
Open
REF
GND
FB REGULATION VOLTAGE (V)
1.8
1.5
1.1
0.75
appear noisy and asynchronous at light-load pulse-
skipping operation, but this is a normal operating con-
dition that results in high light-load efficiency.
Trade-offs in PFM noise and light-load efficiency are
made by varying the inductor value. Generally, low
inductor values produce a broader efficiency vs. load
10
______________________________________________________________________________________
相关PDF资料 |
PDF描述 |
|---|---|
| MAX17085GTL+ | IC CHARGER/CTLR/LDO REG 40-TQFN |
| MAX1708EEE+T | IC REG BST 3.3V/5V/ADJ 5A 16QSOP |
| MAX17094ETM+T | IC REG BOOST ADJ 1A 7OUT 48TQFN |
| MAX1709ESE | IC REG BST 3.3V/5V/ADJ 4A 16SOIC |
| MAX17100ETM+T | IC REG BOOST INT-SWITCH 48-TQFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX17083EVKIT+ | 功能描述:电源管理IC开发工具 Low-Voltage Internal Switch Step-Down 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 |
| MAX17085BETL+ | 功能描述:电池管理 Dual Main Step-Down Controller 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 |
| MAX17085BETL+T | 功能描述:电池管理 Dual Main Step-Down Controller 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 |
| MAX17085BEVKIT+ | 制造商:Maxim Integrated Products 功能描述:STEP-DOWN REGULATOR - Boxed Product (Development Kits) |
| MAX17085GTL+ | 功能描述:电池管理 Dual Main Step-Down Controller 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 |
发布紧急采购，3分钟左右您将得到回复。