MAXIM MAX1917EVKIT

19-2491; Rev 0; 7/02
MAX1917 Evaluation Kit
Features
♦ Automatically Sets VTT and VTTR to 1/2 VDDR
♦ ±1% Output Voltage Accuracy
♦ 2.5V to 14V Input Voltage Range
♦ 7A Output Current Capability
♦ Sourcing and Sinking Current
♦ 550kHz Switching Frequency
♦ 16-Pin QSOP Package
♦ Low-Profile Components
♦ Fully Assembled and Tested
Ordering Information
PART
MAX1917EVKIT
TEMP RANGE
0°C to +70°C
IC PACKAGE
16 QSOP
Component List
DESIGNATION
QTY
C1, C2, C3
3
C4, C5
0
C6–C9
C10, C11
C12
C13, C14
C15
4
2
1
2
1
C16, C17
2
D1
1
J1
1
JU1
1
DESCRIPTION
10µF, 25V X5R ceramic capacitors
(1812)
Taiyo Yuden TMK432BJ106KM or
TDK C4532X5R1E106M
Not installed, E case
270µF, 2V, 15mΩ low-ESR specialty
polymer capacitors, E case
Panasonic EEFUE0E271R
10µF, 6.3V X5R ceramic capacitors
(1206)
Taiyo Yuden JMK212BJ106MG or
TDK C3216X5R0J106M
0.47µF, 25V X5R ceramic capacitor
(1206)
Taiyo Yuden TMK316BJ474ML
0.47µF, 6.3V X5R ceramic capacitors
(0603)
Taiyo Yuden JMK107BJ474MA
4.7µF, 6.3V X5R ceramic capacitor
(0805)
Taiyo Yuden JMK212BJ475MG
1µF, 6.3V X5R ceramic capacitors
(0603)
Taiyo Yuden JMK107BJ105MA
100mA Schottky diode
Central Semiconductor CMPSH-3
Scope probe connector
Berg Electronics 33JR135-1
3-pin header
DESIGNATION
QTY
JU2, JU3
2
2-pin headers
DESCRIPTION
JU4
1
L1
1
N1, N2
2
Q1
1
Q2
0
Not installed
0.8µH, 16A power inductor
Sumida CDEP105L-0R8
N-channel MOSFETs (8-pin SO)
International Rectifier IRF7811W
N-channel MOSFET (SOT23)
Central Semiconductor 2N7002
Not installed, complementary
P-N MOSFETs (SC-89)
Siliconix Si1029X
R1, R5, R7
0
Not installed (0805)
R2
1
5.1kΩ ±5% resistor (0805)
R3
1
100kΩ ±5% resistor (0805)
R4
1
R6
1
0.002Ω ±1%, 1W resistor (2512)
Panasonic ERJM1WTF2M0U
10kΩ ±5% resistor (0805)
R8
0
Not installed (short PC trace) (0805)
R9
1
20Ω ±5% resistor (0805)
U1
1
MAX1917EEE (16-pin QSOP)
None
3
None
4
None
1
Shunts
Rubber bumpers
3M SJ-5007
Mouser 517-SJ-5007BK or equivalent
MAX1917 PC board
None
1
MAX1917 data sheet
None
1
MAX1917 EV kit data sheet
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
Evaluates: MAX1917
General Description
The MAX1917 evaluation kit (EV kit) demonstrates the
MAX1917’s standard 7A application circuit. This DC-DC
converter provides a complete power-management solution for DDR memory. This EV kit is a fully assembled
and tested circuit board. The MAX1917 EV kit generates
a regulated voltage for VTT and VTTR that is half the
voltage at the DDR input. The input voltage range is
2.5V to 14V. The circuit is configured to deliver 7A of
output current. The DC-DC converter uses buck topology
with synchronous rectification to achieve low output
voltage with greater than 90% efficiency. The converter
output is capable of sourcing and sinking current. Sink
capabilities at low voltage arise from the use of a synchronous rectifier, which allows the inductor current to
reverse. The EV kit operates at 550kHz switching frequency and has superior load-transient response that
meets JEDEC specifications for DDR memory.
Evaluates: MAX1917
MAX1917 Evaluation Kit
Component Suppliers
PHONE
FAX
Central Semiconductor
SUPPLIER
516-435-1110
516-435-1824
www.centralsemi.com
WEBSITE
International Rectifier
310-322-3331
310-322-3332
www.irf.com
Panasonic
714-373-7334
714-373-7323
www.panasonic.com
Taiyo Yuden
408-573-4150
408-573-4159
www.t-yuden.com
TDK
847-390-4373
847-390-4428
www.component.tdk.com
Note: Please indicate that you are using the MAX1917 when contacting these component suppliers.
Quick Start
The following equipment is needed:
• 2.5V to 14V power supply (VIN), battery, or notebook
AC adapter
• DC-bias power supply (V+), 5.5V to 14V at 100mA
• Dummy load capable of sourcing/sinking 7A
• Digital multimeter (DMM)
Jumper Settings
Tables 1-4 show jumper settings.
Table 1. Jumper JU1 Functions (POK)
SHUNT LOCATION
1 and 2
2 and 3
• 100MHz dual-trace oscilloscope
The MAX1917 EV kit is a fully assembled and tested
surface-mount board. Follow the steps below to verify
board operation. Do not turn on the power supply
until all connections are completed:
1) Ensure that the circuit is connected correctly to the
supplies and dummy load prior to applying any
power.
2) Verify that the shunts are across JU1 pins 2 and 3,
JU2, and JU3, and not JU4.
POK PIN
Connected to VLOGIC through pullup
resistor R3
Connected to VL through pullup
resistor R3
Table 2. Jumper JU2 Functions
(Switching-Frequency Selection)
JU2
Not Installed
Installed
FSEL PIN
Floating
Connected to GND
FREQUENCY (kHz)
300
550 (as shipped)
Table 3. Jumper JU3 Functions (Fixed/
Adjustable Current-Limit Selection)
3) Apply external reference to the DDR pad.
4) Turn on power supplies and observe the output with
the DMM and/or oscilloscope. Look at the LX
switching node and MOSFET gate-drive signals
while varying the load current.
SHUNT
LOCATION
ON
Detailed Description
The MAX1917 EV kit provides a complete power-management solution for DDR memory. The EV kit is a synchronous, buck-switching, DC-DC converter that
generates half the voltage at the DDR input pad for VTT
and VTTR. The synchronous rectification mode ensures
balanced sourcing and sinking current capability up to
7A. The EV kit operates at 550kHz switching frequency
and has superior line- and load-transient response.
2
OFF
ILIM PIN
Connected to VL.
Connected to GND
through resistor R1
(not provided). Refer
to the Overcurrent
Protection section in
the MAX1917 data
sheet for information
on selecting R1.
CURRENT-LIMIT
THRESHOLD
100mV (default)
Adjustable current
limit
Table 4. Jumper JU4 Functions (V+)
SHUNT
LOCATION
ON
Connected to VL
V+ VOLTAGE
RANGE (V)
4.5 to 5.5
OFF
Not connected to VL
5.5 to 14
V+ PIN
_______________________________________________________________________________________
MAX1917 Evaluation Kit
VLOGIC
1 JU1 3
VL
2
GND
VL
POK
3
R9
20Ω
4
5
Q2-A
OPEN
6
2
1
2
C17
1µF
6.3V
VIN
R5
OPEN
3
Q2-B
OPEN
BST
DDR
EN/HSD
LX
3
15
6
C14
0.47µF
6.3V
REF
6
C13
0.47µF
6.3V
5
12
VTT
5
6
VTTR
ILIM
FSEL
JU2
GND
8
2
J1
3
7
R4
0.002Ω
8
C4
OPEN
C5
OPEN
C6
270µF
2V
N2
4
13
2
C7
270µF
2V
3
R7
OPEN
VOUT
9
VL
R1
OPEN
N1
REF
PGND
GND
8
L1
0.8µH
1
7
7
16
R6
10kΩ
JU3
5
4
MAX1917
DL
C3
10µF
25V
14
U1
Q1
C2
10µF
25V
C1
10µF
25V
C15
4.7µF
6.3V
1
2
REF 2V
2.5V TO 14V
D1
DH
1
1
VIN
VL
11
POK
R2
5.1kΩ
EN
JU4
10
V+
R3
100kΩ
DDR
Evaluates: MAX1917
C12
0.47µF
25V
V+
5.5V TO 14V
VTTR
9
C16
1µF
6.3V
R8
SHORT
(PC TRACE)
C8
270µF
2V
C9
270µF
2V
C10
10µF
6.3V
C11
10µF
6.3V
PGND
FLOAT = 300kHz
GND = 550KHz
Figure 1. MAX1917 EV Kit Schematic
_______________________________________________________________________________________
3
Evaluates: MAX1917
MAX1917 Evaluation Kit
Figure 2. MAX1917EV Kit Component Placement Guide—
Component Side
Figure 3. MAX1917 EV Kit PC Board Layout—Component Side
Figure 4. MAX1917 EV Kit PC Board Layout—Ground Plane
Figure 5. MAX1917 EV Kit PC Board Layout—Solder Side
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
4 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.