MAX17000A_10 Datasheet, PDF (1/32 Pages) Maxim Integrated Products – Complete DDR2 and DDR3 Memory Power-Management Solution

19-4307; Rev 2; 11/10
Complete DDR2 and DDR3 Memory
Power-Management Solution
General Description
The MAX17000A pulse-width modulation (PWM) con-
troller provides a complete power solution for notebook
DDR, DDR2, and DDR3 memory. It comprises a step-
down controller, a source-sink LDO regulator, and a ref-
erence buffer to generate the required VDDQ, VTT, and
VTTR rails.
The VDDQ rail is supplied by a step-down converter
using Maxim’s proprietary Quick-PWM™ controller. The
high-efficiency, constant-on-time PWM controller han-
dles wide input/output voltage ratios (low duty-cycle
applications) with ease and provides 100ns response
to load transients while maintaining a relatively constant
switching frequency. The Quick-PWM architecture cir-
cumvents the poor load-transient timing problems of
fixed-frequency current-mode PWMs while also avoid-
ing the problems caused by widely varying switching
frequencies in conventional constant-on-time and con-
stant-off-time PWM schemes. The controller senses the
current to achieve an accurate valley current-limit pro-
tection. It is also built in with overvoltage, undervoltage,
and thermal protections. The MAX17000A can be set to
run in three different modes: power-efficient SKIP
mode, low-noise forced-PWM mode, and standby
mode to support memory in notebook computer stand-
by operation. The switching frequency is programma-
ble from 200kHz to 600kHz to allow small components
and high efficiency. The VDDQ output voltage can be
set to a preset 1.8V or 1.5V, or be adjusted from 1.0V to
2.5V by an external resistor-divider. This output has 1%
accuracy over line-and-load operating range.
The MAX17000A includes a ±2A source-sink LDO reg-
ulator for the memory termination VTT rail. This VTT reg-
ulator has a ±5mV deadband that either sources or
sinks, ideal for the fast-changing load burst present in
memory termination applications. This feature also
reduces output capacitance requirements.
The VTTR reference buffer sources and sinks ±3mA,
providing the reference voltage needed by the memory
controller and devices on the memory bus.
The MAX17000A is available in a 24-pin, 4mm x 4mm,
thin QFN package.
Applications
Notebook Computers
DDR, DDR2, and DDR3 Memory Supplies
SSTL Memory Supplies
Features
o SMPS Regulator (VDDQ)
Quick-PWM with 100ns Load-Step Response
Output Voltages—Preset 1.8V, 1.5V, or
Adjustable 1.0V to 2.5V
1% V_OUT Accuracy Over Line and Load
26V Maximum Input Voltage Rating
Accurate Valley Current-Limit Protection
200kHz to 600kHz Switching Frequency
o Source/Sink Linear Regulator (VTT)
±2A Peak Source/Sink
Low-Output Capacitance Requirement
Output Voltages-Preset VDDQ/2 or REFIN
Adjustable from 0.5V to 1.5V
o Soft-Start/Soft-Shutdown
o SMPS Power-Good Window Comparator
o VTT Power-Good Window Comparator
o Selectable Overvoltage Protection
o Undervoltage/Thermal Protections
o ±3mA Reference Buffer (VTTR)
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX17000AETG+ -40°C to +85°C 24 Thin QFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Pin Configuration
TOP VIEW
18 17 16 15 14 13
V_DD 19
12 CSL
PGND1 20
11 FB
AGND 21
SKIP 22
MAX17000A
10 REFIN
9 VTTI
V_CC 23
*EP
8 VTT
SHDN 24
7 PGND2
12 3 4 56
Quick-PWM is a trademark of Maxim Integrated Products, Inc.
*EXPOSED PAD
THIN QFN
4mm x 4mm
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.