參數(shù)資料
型號: MAX1718EEI
廠商: MAXIM INTEGRATED PRODUCTS INC
元件分類: 穩(wěn)壓器
英文描述: Notebook CPU Step-Down Controller for Intel Mobile Voltage Positioning IMVP-II
中文描述: SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO28
封裝: 0.150 INCH, 0.025 INCH PITCH, MO-137AD, QSOP-28
文件頁數(shù): 17/35頁
文件大?。?/td> 700K
代理商: MAX1718EEI
M
Notebook CPU Step-Down Controller for Intel
Mobile Voltage Positioning (IMVP-II)
______________________________________________________________________________________
17
(UVLO) circuitry inhibits switching, forces VGATE low,
and forces the DL gate driver high (to enforce output
overvoltage protection). When V
CC
rises above 4.2V, the
DAC inputs are sampled and the output voltage begins
to slew to the DAC setting.
For automatic startup, the battery voltage should be
present before V
CC
. If the MAX1718 attempts to bring
the output into regulation without the battery voltage
present, the fault latch will trip. The SKP/
SDN
pin can
be toggled to reset the fault latch.
Shutdown
When SKP/
SDN
goes low, the MAX1718 enters low-
power shutdown mode. VGATE goes low immediately.
The output voltage ramps down to 0V in 25mV steps at
the clock rate set by R
TIME
. When the DAC reaches the
0V setting, DL goes high, DH goes low, the reference is
turned off, and the supply current drops to about 2μA.
When SKP/
SDN
goes high or floats, the reference pow-
ers up, and after the reference UVLO is passed, the
DAC target is evaluated and switching begins. The
slew-rate controller ramps up from 0V in 25mV steps to
the currently selected code value (based on ZMODE
and SUS). There is no traditional soft-start (variable cur-
rent limit) circuitry, so full output current is available
immediately. VGATE goes high after the slew-rate con-
troller has terminated and the output voltage is in regu-
lation.
UVLO
If V
CC
drops low enough to trip the UVLO comparator, it
is assumed that there is not enough supply voltage to
make valid decisions. To protect the output from over-
voltage faults, DL is forced high in this mode. This will
force the output to GND, but it will not use the slew-rate
controller. This results in large negative inductor current
and possibly small negative output voltages. If V
CC
is
likely to drop in this fashion, the output can be clamped
with a Schottky diode to GND to reduce the negative
excursion.
DAC Inputs D0–D4
The digital-to-analog converter (DAC) programs the
output voltage. It typically receives a preset digital code
from the CPU pins, which are either hard-wired to GND
or left open-circuit. They can also be driven by digital
logic, general-purpose I/O, or an external mux. Do not
leave D0
D4 floating
use 1M
or less pullups if the
inputs may float. D0
D4 can be changed while the
SMPS is active, initiating a transition to a new output
voltage level. If this mode of DAC control is used, connect
ZMODE and SUS low. Change D0
D4 together, avoid-
ing greater than 1μs skew between bits. Otherwise,
incorrect DAC readings may cause a partial transition to
the wrong voltage level, followed by the intended transi-
tion to the correct voltage level, lengthening the overall
transition time. The available DAC codes and resulting
output voltages (Table 3) are compatible with IMVP-II
specification.
Internal Multiplexers (ZMODE, SUS)
The MAX1718 has two unique internal VID input multi-
plexers (muxes) that can select one of three different
VID DAC code settings for different processor states.
Depending on the logic level at SUS, the Suspend
(SUS) mode mux selects the VID DAC code settings
from either the ZMODE mux or the S0/S1 input decoder.
The ZMODE mux selects one of the two VID DAC code
settings from the D0
D4 pins, based on either voltage
on the pins or the output of the impedance decoder
(Figure 9).
When SUS is high, the Suspend mode mux selects the
VID DAC code settings from the S0/S1 input decoder.
The outputs of the decoder are determined by inputs
S0 and S1 (Table 4).
When SUS is low, the Suspend mode mux selects the
output of the ZMODE mux. Depending on the logic level
at ZMODE, the ZMODE mux selects the VID DAC code
settings using either the voltage on D0
D4 or the output
of the impedance decoder (Table 5).
If ZMODE is low, the logic-level voltages on D0
D4 set
the VID DAC settings. This is called Logic mode. In this
mode, the inputs are continuously active and can be
dynamically changed by external logic. The Logic
mode VID DAC code setting is typically used for the
Battery mode state, and the source of this code is
sometimes the VID pins of the CPU with suitable pullup
resistors.
BST
+5V
V
BATT
5
TYP
DH
LX
MAX1718
Figure 8. Reducing the Switching-Node Rise Time
相關(guān)PDF資料
PDF描述
MAX1718 Replaced by TMS320VC5506 : Digital Signal Processors 100-LQFP -40 to 85
MAX1718BEEI Notebook CPU Step-Down Controller for Intel Mobile Voltage Positioning IMVP-II
MAX1720EUTG Switched Capacitor Voltage Inverter with Shutdown
MAX1724EZK50 1.5uA IQ, Step-Up DC-DC Converters in Thin SOT23-5
MAX1724EZK30 1.5uA IQ, Step-Up DC-DC Converters in Thin SOT23-5
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX1718EEI+ 制造商:Maxim Integrated Products 功能描述:LDO CNTRLR STDN 0.6V TO 1.75V 28QSOP - Rail/Tube
MAX1718EEI+T 制造商:Maxim Integrated Products 功能描述:LDO CNTRLR STDN 0.6V TO 1.75V 28QSOP - Tape and Reel
MAX1718EEI-C71059 制造商:Maxim Integrated Products 功能描述:NOTEBOOK CPU STEP-DOWN CONTROLLER FOR INTEL M - Rail/Tube
MAX1718EEI-T 制造商:Maxim Integrated Products 功能描述:NOTEBOOK CPU STEP-DOWN CONTROLLER FOR INTEL M - Tape and Reel
MAX1718EEI-TG068 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: