Datasheet

MAX1917
Tracking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V+ = 12V, V
EN/HSD
= V
DDR
= 2.5V, C
VL
= 4.7µF, C
VTTR
= 1µF, C
REF
= 0.22µF, V
FSEL
= 0, ILIM = VL, PGND = LX = POK = GND,
BST = VL. Specifications are for T
A
= 0°C to +85°C. Typical values are at T
A
= +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 V
BST
+ 0.3V
LX to BST..................................................................-6V to +0.3V
REF Short Circuit to GND ...........................................Continuous
Continuous Power Dissipation (T
A
= +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
PARAMETER CONDITIONS MIN TYP MAX UNITS
5.5 14.0
V+ Input Voltage Range
VL = V+ 4.5 5.5
V
EN/HSD Input Voltage Range Enabled 1.5 15.0 V
DDR Input Voltage Range 0 3.6 V
V+ Supply Current VTT = 2.0V 0.8 1.2 mA
DDR Supply Current 115 250 µA
EN/HSD Supply Current 510µA
VL Supply Current VL = V+ = 5.5V, VTT = 2.0V 0.8 1.2 mA
V+ Shutdown Supply Current EN/HSD = 0V 3 5 µA
DDR Shutdown Supply Current EN/HSD = 0V 1 µA
VL Shutdown Supply Current VL = V+ = 5.5V 3 5 µA
VL Undervoltage Lockout
Threshold
Rising edge, hysteresis = 40mV 4.05 4.25 4.40 V
VTT
VTT Input Bias Current V
VTT
= 2.5V -0.1 0 µA
VTT Feedback Voltage Range 0 1.8 V
Overload range, V
DDR
= 1.8V 49.5 50 50.5
VTT Feedback Voltage
Accuracy
Overload range, V
DDR
= 3.6V 49.5 50 50.5
%V
DDR
REFERENCE
Reference Output Voltage V+ = VL = 4.5V to 5.5V, I
REF
= 0 1.98 2.00 2.02 V
Reference Load Regulation V+ = VL = 5V, I
REF
= 0 to 50µA 10 mV
Reference UVLO V+ = VL = 5V 1.5 1.6 1.7 V
VTTR
VTTR Output Voltage Range 0 1.8 V
I
VTTR
= -5mA to +5mA 49.5 50 50.5
I
VTTR
= -25mA to +25mA, V
DDR
= 1.8V 49 50 51
VTTR Output Accuracy
I
VTTR
= -25mA to +25mA, V
DDR
= 3.6V 49.5 50 50.5
%V
DDR