参数资料
| 型号： | ISL65426HRZ |
| 厂商： | Intersil |
| 文件页数： | 16/22页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK SYNC ADJ 6A DL 50QFN |
| 产品培训模块： | Dual Synchronous Integrated FET Buck Regulator Solutions for Industrial Control Applications |
| 标准包装： | 30 |
| 类型： | 降压（降压） |
| 输出类型： | 可调式 |
| 输出数： | 2 |
| 输出电压： | 1 V ~ 4 V |
| 输入电压： | 3 V ~ 5.5 V |
| PWM 型： | 电流模式 |
| 频率 - 开关： | 1MHz |
| 电流 - 输出： | 6A |
| 同步整流器： | 是 |
| 工作温度： | -10°C ~ 100°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 50-VFQFN 裸露焊盘 |
| 包装： | 管件 |
| 供应商设备封装： | 50-QFN（5x10） |
| 产品目录页面： | 1248 (CN2011-ZH PDF) |
ISL65426
in Table 2. When each pin is pulled to GND by an internal
10μA pull-down, this default condition programs the output
voltage to the lowest level. The pull-down prevents situations
where a pin could be left floating for example (cold solder
joint) from causing the output voltage to rise above the
programmed level and damage a sensitive load device.
TABLE 2. OUTPUT VOLTAGE PROGRAMMING
operation, the power-good signal corresponding to the active
channel changes state from low to high indicating proper
operation initialization.
Power-On Reset
The POR circuitry prevents the controller from attempting to
soft-start before sufficient bias is present at vital power
supply input pins. These include the VCC and PVINx pins.
VOUT1
1.8V
1.5V
1.2V
V1SET1
1
0
1
V1SET2
1
1
0
VOUT2
3.3V
2.5V
1.8V
V2SET1
1
0
1
V2SET2
1
1
0
The VCC pins have a variable POR threshold based on the
output voltage configuration pin configuration of VOUT2. If
the configuration pins are set for 2.5V, the VCC POR rising
threshold is typically 2.9V. The 3.3V configuration increases
the VCC POR level to 4.3V. This variable rising threshold
guarantees that the controller can properly switch the
ISL65426
EXTERNAL CONDITIONS
internal power blocks at the assigned output voltage levels.
The PVINx pins have a set POR rising threshold for all
LX
FB
L OUT
C OUT
V OUT
1.4V
R1
13.3k Ω
R2
10k Ω
output voltage configurations. While the voltage on these
pins are below this threshold (as defined in the “Electrical
Specifications” table), the controller inhibits switching of the
internal power MOSFETs.
Built-in hysteresis between the rising and falling thresholds
insures that once enabled, the controller will not
inadvertently toggle turn off unless the bias voltage drops
substantially. While these pins are below the POR rising
threshold, the synchronous power switch LX pins are held in
FIGURE 36. EXTERNAL OUTPUT VOLTAGE SELECTION
For designers requiring an output voltage level outside those
shown in Table 2, the ISL65426 allows user programming with
an external resistor divider (see Figure 36). First, both channel
selection pins associated with that output channel must be
tied to GND to set the internal reference to 0.6V. Next, the
output voltage is set by an external resistive divider according
to Equation 1. R 2 is selected arbitrarily, but 5k Ω or 10k Ω is
usually a good starting point. The designer can configure the
output voltage from 1V to 4V from a 5V power supply. Lower
input supply voltages reduce the maximum programmable
output voltage to 80% of the input voltage level.
a high-impedance state.
If additional POR control is required, a system enable input
can be used to govern initialization, as described in the
following section.
Enable and Disable
If the POR input requirements are met, the ISL65426
remains in shutdown until the voltage at the enable inputs
rise above their enable thresholds. Independent enable
inputs, EN1 and EN2, allow initialization of either buck
converter channel separately, sequenced, or simultaneously.
Both pins feature a 10μA pull-up, which will initialize both
R 1 = R 2 ? ----------------------------------
V OUT – 0.6V
0.6V
(EQ. 1)
sides once the voltage at their respective pins exceeds the
rising enable threshold, as defined in the “Electrical
Switching Frequency
The controller features an internal oscillator running at a
fixed frequency of 1MHz. The oscillator tolerance is +20%
over input bias and load range.
Operation Initialization
The ISL65426 initializes based on the state of three enable
inputs (EN, EN1, EN2) and power-on reset (POR) monitors
on VCC and PVINx inputs. Successful initialization of the
controller prompts a one time power block configuration
check. Verification of proper phase connections lead to a
soft-start interval. The controller begins slowly ramping the
output voltages based on the enable input states. Once the
commanded output voltage is within the proper window of
16
Specifications” table.
Both converters are governed by the presence of a system
enable, EN. When two separate input supplies are used for
each channel of power blocks or an external signal needs to
govern the power-up sequence, the system enable provides
a start-up sequencing mechanism.
The system enable features an internal 11μA pull-down,
which is only active when the voltage on the EN pin is below
the enable threshold. The current sink pulls the EN pin low.
As VCC2 rises, the enable level is not set exclusively by the
resistor divider from VCC2. With the current sink active, the
FN6340.3
March 25, 2008
相关PDF资料 |
PDF描述 |
|---|---|
| ISL6545IBZ-T | IC REG CTRLR BUCK PWM VM 8-SOIC |
| ISL6548ACRZA-T | IC REG/CTLR ACPI DUAL DDR 28QFN |
| ISL6548CRZA | IC REG/CTRLR ACPI DUAL DDR 28QFN |
| ISL6551IR-T | IC REG CTRLR FLYBACK PWM 28-QFN |
| ISL6552CR-T | IC REG CTRLR BUCK PWM 20-QFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ISL65426HRZS2698 | 制造商:Intersil Corporation 功能描述:LEAD-FREE W/ANNEAL, DUAL BUCK REGULATOR. -10 TO +100 TEMP. - Rail/Tube 制造商:Intersil 功能描述:W/ANNEAL DL BUCKG -10 TO +100 TEMP |
| ISL65426HRZS2715 | 制造商:Intersil Corporation 功能描述:S SPEC FOR TRACKING BROADCOM BUSINESS ONLY-SOLD THRU DISTI - Rail/Tube |
| ISL65426HRZ-T | 功能描述:IC REG BUCK SYNC ADJ 6A DL 50QFN 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 |
| ISL65426HRZ-TS2698 | 制造商:Intersil Corporation 功能描述:LEAD-FREE W/ANNEAL, DUAL BUCK REGULATOR. -10 TO +100 TEMP. - Tape and Reel 制造商:Intersil 功能描述:W/ANNEAL DL BUCKG -10 TO +100 TEMP |
| ISL65426HRZ-TS2715 | 制造商:Intersil Corporation 功能描述:S SPEC FOR TRACKING BROADCOM BUSINESS ONLY-SOLD THRU DISTI - Tape and Reel |
发布紧急采购，3分钟左右您将得到回复。