Datasheet

MAX1917
Tracking, Sinking and Sourcing, Synchronous Buck
Controller for DDR Memory and Termination Supplies
_______________________________________________________________________________________ 7
300
400
350
500
450
600
550
650
157391311 15
FREQUENCY vs. INPUT VOLTAGE
MAX1917 toc07
INPUT VOLTAGE (V)
FREQUENCY (kHz)
CIRCUIT OF FIGURE 3
I
OUT
= 7A
I
OUT
= 0.1A
520
526
524
522
530
528
538
536
534
532
540
-40 -20 0 20 40 60 80 100
FREQUENCY vs. TEMPERATURE
MAX1917 toc08
TEMPERATURE (°C)
FREQUENCY (kHz)
CIRCUIT OF FIGURE 3
I
LOAD
= 3.5A
1.0
2.0
1.5
3.0
2.5
3.5
4.0
1793 5 11 13 15
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX1917 toc09
INPUT VOLTAGE (V)
SHUTDOWN CURRENT (µA)
CIRCUIT OF FIGURE 6
0.5
1.1
0.9
0.7
1.5
1.3
2.3
2.1
1.9
1.7
2.5
13579111315
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX1917 toc10
INPUT VOLTAGE (V)
SHUTDOWN CURRENT (mA)
CIRCUIT OF FIGURE 3
1.22
1.24
1.27
1.26
1.29
1.31
1.30
1.32
-7 -3 -1-5 1357
LOAD REGULATION WITHOUT
DROOP RESISTOR
MAX1917 toc11
LOAD CURRENT (A)
OUTPUT VOLTAGE (V)
V
DDR
= 2.5V
V
IN
= 5V
V
IN
= 12V
V
IN
= 2.5V
1.28
1.23
1.25
1.15
1.17
1.21
1.19
1.23
1.33
1.35
-8 -4 -2-6 02468
LOAD REGULATION WITH
DROOP RESISTOR
MAX1917 toc12
LOAD CURRENT (A)
OUTPUT VOLTAGE (V)
V
DDR
= 2.5V
V
IN
= 12V
V
IN
= 5V
V
IN
= 2.5V
1.25
1.27
1.29
1.31
MAX1917 toc13
I
OUT
5A/div
V
VTT
50mV/div
20µs/div
TRANSIENT LOAD RESPONSE
WITHOUT DROOP RESISTOR
CIRCUIT OF FIGURE 3
OA
MAX1917 toc14
I
OUT
5A/div
V
VTT
50mV/div
20µs/div
TRANSIENT LOAD RESPONSE
WITH DROOP RESISTOR
CIRCUIT OF FIGURE 3
0A
MAX1917 toc15
V
OUT
1V/div
V
POK
5V/div
V
DDR
2.5V
V
EN/HSD
10V/div
400µs/div
POWER-UP WITH V
DDR
TRACKING
Typical Operating Characteristics (continued)
(V+ = 12V, V
OUT
= 1.25V, T
A
= +25°C, unless otherwise noted.)