参数资料
型号: MAX1515ETG+
厂商: Maxim Integrated Products
文件页数: 16/24页
文件大小: 0K
描述: IC REG DDR LV 24-TQFN
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 75
应用: 转换器,DDR
输入电压: 1.3 V ~ 3.6 V
输出数: 2
输出电压: 0.5 V ~ 2.7 V
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
供应商设备封装: 24-TQFN-EP(4x4)
包装: 管件
Low-Voltage, Internal Switch,
Step-Down/DDR Regulator
Table 3. Modes of Operation
SHDN
Low
Low
High
High
High
High
MODE
PIN
Low
High
Low
Low
High
High
SKIP
X
X
Low
High
Low
High
REFOUT
BUFFER
Off, High-Z
On
Off, High-Z
Off, High-Z
On
On
STEP-DOWN
REGULATOR MODE
Off
Off
On, non-DDR mode.
FB regulates to preset voltage or 0.5V.
On, non-DDR mode.
FB regulates to preset voltage or 0.5V.
On, DDR mode.
FB regulates to REFIN.
On, DDR mode.
FB regulates to REFIN.
STEP-DOWN
REGULATOR CURRENT
Off
Off
Source only.
Pulse-skipping mode.
Source/sink.
Forced-PWM mode.
Source/sink.
Pulse-skipping mode.
Source/sink.
Forced-PWM mode.
X = Don’t care.
Pulse Skipping (Source Mode)
Connect SKIP to GND to allow the MAX1515 to auto-
Table 4. Output-Voltage Programming
matically switch between high-efficiency pulse-skipping
mode under light loads and PWM mode under heavy
loads. The transition from PWM mode to pulse-skipping
mode occurs when the load current is half the pulse-
skipping mode current threshold (800mA typ).
In pulse-skipping mode, the switching frequency is
reduced to increase efficiency. The inductor current is
discontinuous in this mode, and the MAX1515 only initi-
FBSEL0
GND
GND
V CC
V CC
FBSEL1
GND
V CC
GND
V CC
OUTPUT
VOLTAGE
Adjustable
V FB = V REFIN
1.5V
1.8V
2.5V
ates an LX switching cycle when V FB < V REFIN . When
V FB falls below V REFIN , the high-side NMOS switch
turns on and remains on until output is in regulation and
the current through the switch increases to the positive
pulse-skipping-mode current threshold (I SKIP_P ) of
800mA. When the high-side NMOS switch turns off, the
low-side NMOS synchronous switch turns on and
remains on until the current through the switch decreas-
es to the zero-cross-current threshold of 200mA.
Pulse Skipping (Sink Mode)
When pulse-skipping operation is selected ( SKIP =
GND) while in DDR mode (MODE = V CC ), the
MAX1515’s source/sink controller switches operating
modes when the output voltage crosses either hys-
teretic sink/source thresholds (V REFIN ±25mV). In
pulse-skipping source mode, the MAX1515 regulates
the valley of the output ripple voltage (see the Pulse
Skipping (Source Mode) section). When the output volt-
age rises above the sink-mode threshold, the MAX1515
enters sink mode. The MAX1515 begins each sink-
mode cycle by turning on the low-side NMOS. The low-
side NMOS remains on until the off-time (t OFF ). After the
low-side NMOS turns off, the high-side NMOS turns on
and remains on until the current through the switch
reaches the zero-cross-current threshold of -350mA. As
long as the output voltage remains below the feedback
threshold, the controller remains in the high-impedance
state. Under light-load conditions, this allows the sink-
mode controller to automatically skip pulses. Under
heavy-load conditions, the output voltage remains
above the feedback threshold, forcing the sink-mode
controller to emulate typical forced-PWM operation.
The pulse-skipping current threshold allows the sink-
mode control scheme to automatically switch between
pulse-skipping PFM and nonskipping PWM operation.
This mechanism forces the boundary between continu-
ous and discontinuous inductor-current operation to be
half the negative pulse-skipping current threshold.
Output Voltage in Non-DDR Mode
In non-DDR mode (MODE = GND and V REFIN = V REF ),
the output of the MAX1515 is selectable between one
of three preset output voltages: 2.5V, 1.8V, and 1.5V.
For a preset output voltage, connect FB to the output
voltage and connect FBSEL0 and FBSEL1 as indicated
in Table 4. For an adjustable output voltage, connect
FBSEL0 and FBSEL1 to GND and connect REFIN to a
16
______________________________________________________________________________________
相关PDF资料
PDF描述
MAX1518BETJ+T IC DC-DC CONV TFT-LCD 32-TQFN
MAX1524EUT-T IC REG CTRLR BST FLYBK SOT23-6
MAX15301ETJ+ IC REG CTRLR BUCK 32TQFN
MAX1531ETJ+T IC PS CTRLR MULTI-OUTPUT 32TQFN
MAX1531ETJ/V+T IC PS CTRLR MULTI-OUTPUT 32WQFN
相关代理商/技术参数
参数描述
MAX1515ETG+ 功能描述:直流/直流开关调节器 3A 1MHz Step-Down DDR Regulator RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5
MAX1515ETG+T 功能描述:直流/直流开关调节器 3A 1MHz Step-Down DDR Regulator RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5
MAX1515ETG-T 功能描述:直流/直流开关调节器 RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5
MAX1515EVKIT 制造商:Maxim Integrated Products 功能描述:3A 1MHZ LOW-VOLTAGE INTERNAL SWI - Rail/Tube
MAX15166EWE+ 制造商:Maxim Integrated Products 功能描述:HIGH-EFFICIENCY, 4A, STEP-DOWN DC-DC REGULATOR WITH INTERNAL - Rail/Tube