MAX1917EEE ,Tracking / Sinking and Sourcing / Synchronous Buck Controller for DDR Memory and Termination SuppliesELECTRICAL CHARACTERISTICS(V+ = 12V, V = V = 2.5V, C = 4.7µF, C = 1µF, C = 0.22µF, V = 0, ILIM = VL ..
MAX1917EEE+ ,Tracking, Sinking and Sourcing, Synchronous Buck Controller for DDR Memory and Termination SuppliesApplicationsDDR Memory Power Notebook ComputersOrdering InformationSupplyDesktop ComputersPART TEMP ..
MAX1917EEE+T ,Tracking, Sinking and Sourcing, Synchronous Buck Controller for DDR Memory and Termination SuppliesMAX191719-2335; Rev 1; 6/02Tracking, Sinking and Sourcing, Synchronous BuckController for DDR Memor ..
MAX1917EEE+T ,Tracking, Sinking and Sourcing, Synchronous Buck Controller for DDR Memory and Termination SuppliesFeaturesThe MAX1917 provides a complete power-manage-♦ 25A Sourcing and Sinking Currentment solutio ..
MAX1917EEE-T ,Tracking, Sinking and Sourcing, Synchronous Buck Controller for DDR Memory and Termination SuppliesELECTRICAL CHARACTERISTICS(V+ = 12V, V = V = 2.5V, C = 4.7µF, C = 1µF, C = 0.22µF, V = 0, ILIM = VL ..
MAX191ACWG ,Low-Power / 12-Bit Sampling ADC with Internal Reference and Power-DownFeatures
. 12-Bit Resolution, 1/2LSB Linearity
. +5V or 15V Operation (MAX191)
. Built-InT ..
MAX487EEPA ,15kV ESD-Protected / Slew-Rate-Limited / Low-Power / RS-485/RS-422 TransceiversFeaturesThe MAX481E, MAX483E, MAX485E, MAX487E–MAX491E, ' ESD Protection: ±15kV—Human Body Modelan ..
MAX487EEPA+ ,±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 TransceiversELECTRICAL CHARACTERISTICS(V = 5V ±5%, T = T to T , unless otherwise noted.) (Notes 1, 2)CC A MIN M ..
MAX487EESA ,15kV ESD-Protected / Slew-Rate-Limited / Low-Power / RS-485/RS-422 TransceiversApplicationsIndustrial-Control Local Area Networks__Selection TableRECEIVER/ QUIESCENT NUMBER OFPAR ..
MAX487EESA ,15kV ESD-Protected / Slew-Rate-Limited / Low-Power / RS-485/RS-422 Transceiversapplications. For
MAX487EESA ,15kV ESD-Protected / Slew-Rate-Limited / Low-Power / RS-485/RS-422 TransceiversApplicationsMAX481EESA -40°C to +85°C 8 SOLow-Power RS-485 TransceiversOrdering Information continu ..
MAX487EESA ,15kV ESD-Protected / Slew-Rate-Limited / Low-Power / RS-485/RS-422 TransceiversApplicationsMAX481EESA -40°C to +85°C 8 SOLow-Power RS-485 TransceiversOrdering Information continu ..
MAX1917EEE
Tracking / Sinking and Sourcing / Synchronous Buck Controller for DDR Memory and Termination Supplies
General DescriptionThe MAX1917 provides a complete power-manage-
ment solution for DDR memory. It contains a synchro-
nous buck controller and an amplifier to generate
1/2VDDRvoltage for VTT and VTTR. The VTT and VTTR
voltages are maintained within 1% of 1/2VDDR. The
controller operates in synchronous rectification mode to
ensure balanced current sourcing and sinking capabili-
ty of up to 25A. With a shutdown current of less than
5µA, the MAX1917 is the best choice for low-power
notebook applications, as well as servers and desktop
computers. An all N-FET design optimizes efficiency.
The MAX1917 can also be used for generating VDDR
and as a general-purpose step-down controller with
variable switching frequency as high as 1MHz with few
additional components.
The MAX1917 uses Maxim’s proprietary Quick-PWM™
architecture for fast transient response up to 96% effi-
ciency, and the smallest external components. Output
current monitoring is achieved without sense resistors
by monitoring the bottom FET’s drain-to-source voltage.
The current-limit threshold is programmable through an
external resistor. The MAX1917 comes in a space-sav-
ing 16-pin QSOP package.
Applications
Features25A Sourcing and Sinking CurrentAutomatically Sets VTT to 1/2VDDRVTT and VTTR Within 1% of 1/2VDDRSmallest Output Capacitors4.5V to 14V (or 28V with Resistor-Divider) Input
Voltage Range1.5V to 3.6V Input DDR Range 200kHz/300kHz/400kHz/550kHz Preset Switching
FrequenciesVariable Switching Frequency of Up to 1MHzOvercurrent Protection Without Current-Sense
ResistorInternal Soft-StartVTTR Reference Sources and Sinks Up to 25mAQuick-PWM Control for Fastest Loop ResponseUp to 96% Efficiency16-Pin QSOP Package
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
Ordering Informationypical Operating Circuit19-2335; Rev 1; 6/02
Pin ConfigurationQuick-PWM is a trademark of Maxim Integrated Products, Inc.
DDR Memory Power
Supply
Processor or DSP Core
Supply
AGTL Bus Termination
Supply
Notebook Computers
Desktop Computers
Storage
Networking Systems
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(V+ = 12V, VEN/HSD= VDDR= 2.5V, CVL= 4.7µF, CVTTR= 1µF, CREF= 0.22µF, VFSEL= 0, ILIM = VL, PGND = LX = POK = GND,
BST = VL. Specifications are for TA
= 0°C to +85°C. Typical values are at TA= +25°C, unless otherwise specified.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
V+ to GND..............................................................-0.3V to +15V
EN/HSD to GND.....................................................-0.3V to +16V
VL to GND................................................................-0.3V to +6V
PGND to GND.......................................................-0.3V to +0.3V
VTT, DDR, POK to GND...........................................-0.3V to +6V
REF, VTTR, DL, ILIM, FSEL to GND................-0.3V to VL + 0.3V
LX to PGND............................................................-0.3V to +30V
BST to GND............................................................-0.3V to +36V
DH to LX......................................................-0.3V to VBST+ 0.3V
LX to BST..................................................................-6V to +0.3V
REF Short Circuit to GND...........................................Continuous
Continuous Power Dissipation (TA= +70°C)
16-Pin QSOP (derate up to +70°C)..............................667mW
16-Pin QSOP (derating above +70°C).....................8.3mW/°C
Operating Temperature Range
Extended.........................................................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering 10s.).................................+300°C
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
ELECTRICAL CHARACTERISTICS (continued)(V+ = 12V, VEN/HSD= VDDR= 2.5V, CVL= 4.7µF, CVTTR= 1µF, CREF= 0.22µF, VFSEL= 0, ILIM = VL, PGND = LX = POK = GND,
BST = VL. Specifications are for TA
= 0°C to +85°C. Typical values are at TA= +25°C, unless otherwise specified.)
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
ELECTRICAL CHARACTERISTICS (continued)(V+ = 12V, VEN/HSD= VDDR= 2.5V, CVL= 4.7µF, CVTTR= 1µF, CREF= 0.22µF, VFSEL= 0, ILIM = VL, PGND = LX = POK = GND,
BST = VL. Specifications are for TA
= 0°C to +85°C. Typical values are at TA= +25°C, unless otherwise specified.)
ELECTRICAL CHARACTERISTICS(V+ = 12V, VEN/HSD= VDDR= 2.5V, CVL= 4.7µF, CVTTR= 1µF, CREF= 0.22µF, VFSEL= 0, ILIM = VL, PGND = LX = POK = GND,
BST = VL. Specifications are for TA
= -40°C to +85°C, unless otherwise specified.) (Note 2)
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 12V, VEN/HSD= VDDR= 2.5V, CVL= 4.7µF, CVTTR= 1µF, CREF= 0.22µF, VFSEL= 0, ILIM = VL, PGND = LX = POK = GND,
BST = VL. Specifications are for TA
= -40°C to +85°C, unless otherwise specified.) (Note 2)
Note 1:On Time and Off Time specifications are measured from 50% point to 50% point at the DH pin with LX forced to 0V, BST
forced to 5V, and a 250pF capacitor connected from DH to LX. Actual in-circuit times may differ due to MOSFET switching
speeds.
Note 2:Specifications to -40°C are guaranteed by design and are not production tested.
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 12V, VEN/HSD= VDDR= 2.5V, CVL= 4.7µF, CVTTR= 1µF, CREF= 0.22µF, VFSEL= 0, ILIM = VL, PGND = LX = POK = GND,
BST = VL. Specifications are for TA= -40°C to +85°C, unless otherwise specified.) (Note 2)
EFFICIENCY vs. LOAD CURRENT
AT 1.25V OUTPUTMAX1917 toc01
LOAD CURRENT (A)
EFFICIENCY (%)70
EFFICIENCY vs. LOAD CURRENT
AT 0.9V OUTPUT
MAX1917 toc02
LOAD CURRENT (A)
EFFICIENCY (%)84
EFFICIENCY vs. LOAD CURRENT
AT 1.25V OUTPUT
MAX1917 toc03
LOAD CURRENT (A)
EFFICIENCY (%)40
EFFICIENCY vs. LOAD CURRENT
AT 0.9V OUTPUT
MAX1917 toc04
EFFICIENCY (%)65
FREQUENCY vs. LOAD CURRENT
AT 1.25V OUTPUT
MAX1917 toc05
FREQUENCY (kHz)
FREQUENCY vs. LOAD CURRENT
AT 0.9V OUTPUT
MAX1917 toc06
FREQUENCY (kHz)
Typical Operating Characteristics(V+ = 12V, VOUT= 1.25V, TA= +25°C, unless otherwise noted.)
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination SuppliesFREQUENCY vs. INPUT VOLTAGE
MAX1917 toc07
INPUT VOLTAGE (V)
FREQUENCY (kHz)
FREQUENCY vs. TEMPERATURE
MAX1917 toc08
TEMPERATURE (°C)
FREQUENCY (kHz)
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX1917 toc09
INPUT VOLTAGE (V)
SHUTDOWN CURRENT (
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX1917 toc10
INPUT VOLTAGE (V)
SHUTDOWN CURRENT (mA)1.22
LOAD REGULATION WITHOUT
DROOP RESISTOR
MAX1917 toc11
LOAD CURRENT (A)
OUTPUT VOLTAGE (V)
LOAD REGULATION WITH
DROOP RESISTOR
MAX1917 toc12
LOAD CURRENT (A)
OUTPUT VOLTAGE (V)
MAX1917 toc13
IOUT
5A/div
VVTT
50mV/div
20µs/div
TRANSIENT LOAD RESPONSE
WITHOUT DROOP RESISTORMAX1917 toc14
IOUT
5A/div
VVTT
50mV/div
20µs/div
TRANSIENT LOAD RESPONSE
WITH DROOP RESISTORMAX1917 toc15
VOUT
1V/div
VPOK
5V/div
VDDR
2.5V
VEN/HSD
10V/div
400µs/div
POWER-UP WITH VDDR TRACKING
Typical Operating Characteristics (continued)(V+ = 12V, VOUT= 1.25V, TA= +25°C, unless otherwise noted.)
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
CURRENT LIMIT vs. TEMPERATUREMAX1917 toc16
TEMPERATURE (°C)
CURRENT LIMIT (A)6020400-20
MAX1917 toc17
VIN (V)
INDUCTOR CURRENT (A)119753
INDUCTOR PEAK AND VALLEY CURRENT
vs. INPUT VOLTAGE AT CURRENT LIMITypical Operating Characteristics (continued)
(V+ = 12V, VOUT= 1.25V, TA= +25°C, unless otherwise noted.)
MAX1917racking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
Functional Diagram
