- 您现在的位置：买卖IC网 > Datasheet目录334 > ISL8501EVAL1Z (Intersil)EVALUATION BOARD FOR ISL8501 Datasheet资料下载
参数资料
| 型号： | ISL8501EVAL1Z |
| 厂商： | Intersil |
| 文件页数： | 18/19页 |
| 文件大小： | 0K |
| 描述： | EVALUATION BOARD FOR ISL8501 |
| 标准包装： | 1 |
| 主要目的： | DC/DC，LDO 步降 |
| 输出及类型： | 3，非隔离 |
| 输出电压： | 3.3V，1.2V，1.8V |
| 电流 - 输出： | 1A，500mA，500mA |
| 输入电压： | 4.5 ~ 25 V |
| 稳压器拓扑结构： | 降压 |
| 频率 - 开关： | 500kHz |
| 板类型： | 完全填充 |
| 已供物品： | 板 |
| 已用 IC / 零件： | ISL8501 |
ISL8501
The compensation gain uses external impedance networks
Z FB and Z IN to provide a stable, high bandwidth (BW) overall
loop. A stable control loop has a gain crossing with
-20dB/decade slope and a phase margin greater than 45°.
Include worst case component variations when determining
phase margin.
A more detailed explanation of voltage mode control of a
buck regulator can be found in Tech Brief TB417, titled
“Designing Stable Compensation Networks for Single Phase
Voltage Mode Buck Regulators.”
represent numerous physical capacitors. Dedicate one solid
layer (usually a middle layer of the PC board) for a ground
plane and make all critical component ground connections
with vias to this layer. Dedicate another solid layer as a
power plane and break this plane into smaller islands of
common voltage levels. Keep the metal runs from the
PHASE terminals to the output inductor short. The power
plane should support the input power and output power
nodes. Use copper filled polygons on the top and bottom
circuit layers for the phase nodes. Use the remaining printed
circuit layers for small signal wiring.
100
f Z1 f Z2
f P1
f P2
In order to dissipate heat generated by the internal LDO and
80
MOSFET, the ground pad, pin 29, should be connected to
60
40
20LOG
OPEN LOOP
ERROR AMP GAIN
the internal ground plane through at least four vias. This
allows the heat to move away from the IC and also ties the
pad to the ground plane through a low impedance path.
20
0
(R 2 /R 1 )
20LOG
(V IN / Δ V OSC )
The switching components should be placed close to the
ISL8501 first. Minimize the length of the connections
-20
-40
-60
MODULATOR
GAIN
f LC
f ESR
COMPENSATION
GAIN
CLOSED LOOP
GAIN
between the input capacitors, C IN , and the power switches
by placing them nearby. Position both the ceramic and bulk
input capacitors as close to the upper MOSFET drain as
possible. Position the output inductor and output capacitors
10
100
1k
10k
100k
1M
10M
between the upper and lower MOSFETs and the load.
FREQUENCY (Hz)
FIGURE 33. ASYMPTOTIC BODE PLOT OF CONVERTER GAIN
Layout Considerations
Layout is very important in high frequency switching
converter design. With power devices switching efficiently at
500kHz, the resulting current transitions from one device to
another cause voltage spikes across the interconnecting
The critical small signal components include any bypass
capacitors, feedback components, and compensation
components. Place the PWM converter compensation
components close to the FB and COMP pins. The feedback
resistors should be located as close as possible to the FB
pin with vias tied straight to the ground plane as required.
impedances and parasitic circuit elements. These voltage
spikes can degrade efficiency, radiate noise into the circuit,
and lead to device overvoltage stress. Careful component
layout and printed circuit board design minimizes these
5V
C BP1
PVCC
ISL8501
VIN
V IN
C IN
voltage spikes.
As an example, consider the turn-off transition of the upper
MOSFET. Prior to turn-off, the MOSFET is carrying the full
R BP
C BP2
VCC
PHASE
PGND
D
L
C OUT1
V OUT1
load current. During turn-off, current stops flowing in the
MOSFET and is picked up by the Schottky diode. Any
parasitic inductance in the switched current path generates a
large voltage spike during the switching interval. Careful
COMP
C 2
R 2
C 1
R 1
component selection, tight layout of the critical components,
FB
and short, wide traces minimizes the magnitude of voltage
R 4
C 3
R 3
spikes.
GND PAD
There are two sets of critical components in the ISL8501
switching converter. The switching components are the most
critical because they switch large amounts of energy, and
therefore tend to generate large amounts of noise. Next are
the small signal components, which connect to sensitive
nodes or supply critical bypass current and signal coupling.
A multi-layer printed circuit board is recommended. Figure 34
shows the connections of the critical components in the
converter. Note that capacitors C IN and C OUT could each
18
KEY
ISLAND ON POWER PLANE LAYER
ISLAND ON CIRCUIT AND/OR POWER PLANE LAYER
VIA CONNECTION TO GROUND PLANE
FIGURE 34. PRINTED CIRCUIT BOARD POWER PLANES
AND ISLANDS
FN6500.1
July 12, 2007
相关PDF资料 |
PDF描述 |
|---|---|
| ISL8510EVAL1Z | EVALUATION BOARD FOR ISL8510 |
| ISL89162FBEBZ | IC MOSFET DRIVER 2CH 6A 8SOIC |
| ISL89165FBECZ | MOSFET DRIVER 2CH 6A 8SOIC |
| ISL89168FBEAZ | IC MOSFET DRIVER 2CH 6A 8SOIC |
| ISL89367FRTAZ | IC MOSFET DRIVER 2CH 6A 16TDFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ISL8501IRZ | 功能描述:电压模式 PWM 控制器 INTEGRTD FETUCK 4X 4 24LD W/ANNEAL 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 |
| ISL8501IRZ-T | 功能描述:电压模式 PWM 控制器 INTEGRTD FETUCK 4X 4 24LD W/ANNEAL 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 |
| ISL8502AEVAL1Z | 功能描述:EVAL BOARD FOR ISL8502 RoHS:是 类别:编程器，开发系统 >> 评估板 - DC/DC 与 AC/DC（离线）SMPS 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:True Shutdown™ 主要目的:DC/DC，步升 输出及类型:1，非隔离 功率 - 输出:- 输出电压:- 电流 - 输出:1A 输入电压:2.5 V ~ 5.5 V 稳压器拓扑结构:升压 频率 - 开关:3MHz 板类型:完全填充 已供物品:板 已用 IC / 零件:MAX8969 |
| ISL8502AIRZ | 功能描述:IC REG BUCK SYNC ADJ 2A 24QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 类型:降压（降压） 输出类型:两者兼有 输出数:1 输出电压:5V，1 V ~ 10 V 输入电压:3.5 V ~ 28 V PWM 型:电流模式 频率 - 开关:220kHz ~ 1MHz 电流 - 输出:600mA 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:16-SSOP（0.154"，3.90mm 宽） 包装:带卷 (TR) 供应商设备封装:16-QSOP |
| ISL8502AIRZ-T | 功能描述:IC REG BUCK SYNC ADJ 2A 24QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 类型:降压（降压） 输出类型:两者兼有 输出数:1 输出电压:5V，1 V ~ 10 V 输入电压:3.5 V ~ 28 V PWM 型:电流模式 频率 - 开关:220kHz ~ 1MHz 电流 - 输出:600mA 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:16-SSOP（0.154"，3.90mm 宽） 包装:带卷 (TR) 供应商设备封装:16-QSOP |
发布紧急采购，3分钟左右您将得到回复。