Tracking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
MAX1917
ABSOLUTE MAXIMUM RATINGS
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
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.
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.)
PARAMETER
V+ Input Voltage Range
EN/HSD Input Voltage Range
DDR Input Voltage Range
V+ Supply Current
DDR Supply Current
EN/HSD Supply Current
VL Supply Current
V+ Shutdown Supply Current
DDR Shutdown Supply Current
VL Shutdown Supply Current
VL Undervoltage Lockout
Threshold
VTT
VTT Input Bias Current
VTT Feedback Voltage Range
VTT Feedback Voltage
Accuracy
REFERENCE
Reference Output Voltage
Reference Load Regulation
Reference UVLO
VTTR
VTTR Output Voltage Range
I
VTTR
= -5mA to +5mA
VTTR Output Accuracy
I
VTTR
= -25mA to +25mA, V
DDR
= 1.8V
I
VTTR
= -25mA to +25mA, V
DDR
= 3.6V
0
49.5
49
49.5
50
50
50
1.8
50.5
51
50.5
%V
DDR
V
V+ = VL = 4.5V to 5.5V, I
REF
= 0
V+ = VL = 5V, I
REF
= 0 to 50µA
V+ = VL = 5V
1.5
1.6
1.98
2.00
2.02
10
1.7
V
mV
V
Overload range, V
DDR
= 1.8V
Overload range, V
DDR
= 3.6V
V
VTT
= 2.5V
-0.1
0
49.5
49.5
50
50
0
1.8
50.5
50.5
µA
V
%V
DDR
VL = V+ = 5.5V, VTT = 2.0V
EN/HSD = 0V
EN/HSD = 0V
VL = V+ = 5.5V
Rising edge, hysteresis = 40mV
4.05
3
4.25
VTT = 2.0V
VL = V+
Enabled
CONDITIONS
MIN
5.5
4.5
1.5
0
0.8
115
5
0.8
3
TYP
MAX
14.0
5.5
15.0
3.6
1.2
250
10
1.2
5
1
5
4.40
UNITS
V
V
V
mA
µA
µA
mA
µA
µA
µA
V
2
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
