- 您现在的位置：买卖IC网 > PDF目录1840 > MAX17528GTJ+T (Maxim Integrated Products)IC CTLR PWM VID PS 1PH 32-TQFN PDF资料下载
参数资料
| 型号： | MAX17528GTJ+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 36/41页 |
| 文件大小： | 0K |
| 描述： | IC CTLR PWM VID PS 1PH 32-TQFN |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 系列： | Quick-PWM™ |
| 应用： | 控制器，Intel IMVP-6.5? GMCH |
| 输入电压： | 4.5 V ~ 5.5 V |
| 输出数： | 1 |
| 输出电压： | 0.01 V ~ 1.5 V |
| 工作温度： | -40°C ~ 105°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 32-WFQFN 裸露焊盘 |
| 供应商设备封装： | 32-TQFN-EP（5x5） |
| 包装： | 带卷 (TR) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页当前第36页第37页第38页第39页第40页第41页
1-Phase Quick-PWM
Intel IMVP-6.5/GMCH Controllers
(
) 2
? ? + t OFF (M IN ) ?
? ? V OUT t SW ? ?
? ?
V SAG =
? ? ( V IN ? V OUT ) t SW ? ?
2 C OUT V OUT ? ? ? ? t OFF ( MIN ) ?
? ? ?
? ?
≈ ( ? I LOAD ( MAX ) ) 2 L
?
?
Switching frequency: This choice determines the
basic trade-off between size and efficiency. The
optimal frequency is largely a function of maximum
input voltage due to MOSFET switching losses that
are proportional to frequency and V IN 2 . The opti-
mum frequency is also a moving target due to rapid
improvements in MOSFET technology that are mak-
ing higher frequencies more practical.
Inductor operating point: This choice provides
trade-offs between size vs. efficiency and transient
response vs. output noise. Low inductor values pro-
vide better transient response and smaller physical
size, but also result in lower efficiency and higher
output noise due to increased ripple current. The
L ? I LOAD(MAX) ? ? M
V IN ?
V IN
where t OFF(MIN) is the minimum off-time (see the
Electrical Characteristics table).
The amount of overshoot due to stored inductor energy
can be calculated as:
V SOAR
2 C OUT V OUT
dV TARGET / dt = 12 . 5 mV / μs × ?
minimum practical inductor value is one that causes
the circuit to operate at the edge of critical conduc-
tion (where the inductor current just touches zero
with every cycle at maximum load). Inductor values
lower than this grant no further size-reduction bene-
fit. The optimum operating point is usually found
between 20% and 50% ripple current.
Inductor Selection
The switching frequency and operating point (% ripple
current or LIR) determine the inductor value as follows:
Current-Limit and Slew-Rate Control
(TIME and ILIM)
TIME and ILIM are used to control the slew rate and
current limit. TIME regulates to a fixed 2.0V. The
MAX17528 uses the TIME source current to set the
slew rate (dV TARGET /dt). The higher the source current,
the faster the nominal output-voltage slew rate:
? 71.5k ? ?
? R TIME ? ?
L = ?
f SW LOAD ( MAX ) LIR ? ? ? V IN ? ?
?
?
?
I
V IN ? V OUT ? ? V OUT ?
where R TIME is the sum of resistance values between
TIME and ground.
I PEAK LOAD ( MAX ) ? 1 +
= I
?
V LIMIT = TIME ILIM
Find a low-loss inductor having the lowest possible DC
resistance that fits in the allotted dimensions. Molded
cores are often the best choice, although powdered
iron and ferrite cores are inexpensive and can work
well at 300kHz. The core must be large enough not to
saturate at the peak inductor current (I PEAK ):
? LIR ?
? 2 ?
Transient Response
The inductor ripple current impacts transient-response
performance, especially at low V IN - V OUT differentials.
Low inductor values allow the inductor current to slew
faster, replenishing charge removed from the output fil-
ter capacitors by a sudden load step. The amount of
output sag is also a function of the maximum duty fac-
tor, which can be calculated from the on-time and mini-
mum off-time. The worst-case output sag voltage can
be determined by:
The ILIM voltage determines the valley current-sense
threshold. When ILIM = V CC , the controller uses the
preset 22.5mV (typ) current-limit threshold. In an
adjustable design, ILIM is connected to a resistive volt-
age-divider connected between TIME and ground. The
differential voltage between TIME and ILIM sets the
current-limit threshold (V LIMIT ), so the valley current-
sense threshold is:
V ? V
10
where the V LIMIT tolerances are defined in the Electrical
Characteristics table.
This allows design flexibility since the DCR sense cir-
cuit or sense resistor does not have to be adjusted to
meet the current limit as long as the current-sense volt-
age never exceeds 50mV. Keeping V LIMIT between
20mV to 40mV leaves room for future current-limit
adjustment.
36
______________________________________________________________________________________
相关PDF资料 |
PDF描述 |
|---|---|
| MAX17535ETG+T | IC SMBUS BATT CHARGER 24TQFN |
| MAX1757EAI+T | IC BATTERY CHRG LI+ 28-SSOP |
| MAX17582GTM+T | IC CTLR PWM 2PH IMVP-6.5 48-TQFN |
| MAX1758EAI+T | IC BATTERY CHRG LI+ 28-SSOP |
| MAX1759EUB | IC REG MULTI CONFIG 0.1A 10UMAX |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX17535ETG+ | 功能描述:电池管理 High Frequency SMBus Charger 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 |
| MAX17535ETG+T | 功能描述:电池管理 High Frequency SMBus Charger 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 |
| MAX17535EVKIT+ | 功能描述:电池管理 EVKIT 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 |
| MAX17552ATB+T | 制造商:Maxim Integrated Products 功能描述: |
| MAX1756AAUT | 制造商:Maxim Integrated Products 功能描述:- Cut Tape Product |
发布紧急采购，3分钟左右您将得到回复。