MAXIM MAX1549

19-3299; Rev 0; 5/04
MAX1549 Evaluation Kit
Features
The MAX1549 evaluation kit (EV kit) demonstrates the
MAX1549’s standard application circuit. This DC-DC
converter steps down high-voltage batteries and/or AC
adapters, generating precision low-voltage chipset and
RAM power supplies for notebook computers.
The MAX1549 EV kit provides a dynamically adjustable
0.7V to 1.5V output voltage range (OUT1), and a fixed
2.5V output voltage (OUT2) from a 5V to 20V battery
input range. It delivers up to a 6A output current for
OUT1, and up to a 4A output current for OUT2, with
greater than 90% efficiency. The EV kit operates at
300kHz switching frequency and has superior line- and
load-transient response.
♦ 5V to 20V Input Voltage Range
This EV kit is a fully assembled and tested circuit
board. It is capable of evaluating other dynamically
adjustable output voltages in the 0.5V to 2.0V range by
changing R10–R14. Other fixed output voltages in the
0.5V to 2.7V range can be evaluated by changing R20
and R21.
♦ 300kHz Switching Frequency
♦ Four Digitally Selectable Operating Voltages
(OUT1)
♦ Dynamically Selectable Output Voltages
0.7V/1.0V/1.3V/1.5V (OUT1, Adjustable from 0.5V
to 2.0V)
♦ Fixed 2.5V Output Voltage (OUT2, Adjustable from
0.5V to 2.7V)
♦ 6A Output Current (OUT1)
♦ 4A Output Current (OUT2)
♦ Independent Power-Good Outputs
♦ Low-Profile Components
♦ Fully Assembled and Tested
Ordering Information
PART
TEMP RANGE
o
MAX1549EVKIT
o
0 C to +70 C
IC PACKAGE
40 Thin QFN
(6mm x 6mm)
Component List
DESIGNATION
QTY
C1, C19
0
C2
1
DESCRIPTION
470µF, 2.5V, 6mΩ low-ESR polymer
capacitor (E-case)
Sanyo 2R5TPD470M6
220µF, 4V, 15mΩ low-ESR
capacitor (D-case)
Sanyo 4TPE220MF
C4, C5
2
10µF ±20%, 25V X5R ceramic
capacitors (1812)
Taiyo Yuden TMK432BJ106KM or
TDK C4532X5R1E106M
C6, C7
0
Not installed (1812)
2
0.1µF ±10%, 50V X7R ceramic
capacitors (0603)
Murata GRM188R71H104K or
equivalent
C8, C9
C10, C11,
C20–C26
0
QTY
C12
1
2.2µF, 10V X5R ceramic capacitor
(0612)
TDK C1632X5R1A225KTB09N
C13, C16
2
470pF ±10%, 50V X7R ceramic
capacitors (0603)
Murata GRM188R71H471K or
equivalent
C14
1
0.22µF, 16V X5R ceramic capacitor
(0805)
Taiyo Yuden EMK212BJ224KG
1
1µF ±20%, 10V X5R ceramic
capacitor (0805)
Taiyo Yuden LMK212BJ105KG or
TDK C2012X7R1C105MKT
2
100pF ±5%, 50V C0G ceramic
capacitors (0603)
Murata GRM1885C1H101J or
equivalent
Not installed (E-case)
1
C3
DESIGNATION
Not installed (0603)
C15
C17, C18
DESCRIPTION
________________________________________________________________ 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: MAX1549
General Description
MAX1549 Evaluation Kit
Evaluates: MAX1549
Component List (continued)
DESIGNATION
C27, C28
D1, D2
D3
QTY
DESCRIPTION
2
10µF ±20%, 6.3V X5R ceramic
capacitors (0805)
TDK C2012X5R0J106M or
Taiyo Yuden AMK212BJ106MG
2
1A, 30V Schottky diodes
Nihon EP10QY03 or
Toshiba CRS02
1
100mA, 30V dual Schottky diode
(SOT23)
Central Semiconductor CMPSH-3A
DESIGNATION
QTY
DESCRIPTION
R1
1
0.012Ω ±1%, 0.5W resistor (2010)
IRC LR2010-01-R012-F or
Dale WSL-2010-R012F
R2
1
0.015Ω ±1%, 0.5W resistor (2010)
IRC LR2010-01-R015-F or
Dale WSL-2010-R015F
R3–R6, R22, R23
0
Not installed (short PC trace)
(0603)
R7, R8, R27, R28
4
100kΩ ±5% resistors (0603)
R9
1
10Ω ±5% resistor (0805)
JU1, JU2, JU6
3
3-pin headers
R10, R15–R18
5
100kΩ ±1% resistors (0603)
JU3
0
Not installed, 4-pin header
R11
1
301kΩ ±1% resistor (0603)
JU4, JU5
2
2-pin headers
R12
1
487kΩ ±1% resistor (0603)
JU1 (1,2) JU2
(1,2) JU6 (1,2)
4
Shunts
R13
1
150kΩ ±1% resistor (0603)
R14
1
66.5kΩ ±1% resistor (0603)
R19, R20, R24,
R25, R26, R29,
R32
0
Not installed (0603)
R21
1
0Ω ±1% resistor (0603)
U1
1
MAX1549ETL
(40-pin thin QFN 6mm x 6mm)
None
4
Rubber bumpers
None
1
MAX1549 PC board
L1
L2
1
1.5µH, 7A power inductor
Sumida CDRH105R-1R5
1
4.7µH, 5.7A power inductor
Sumida CDRH124-4R7
N1, N3
2
N-channel MOSFETs (8-pin SO)
Fairchild FDS6612A
N2, N4
2
N-channel MOSFETs (8-pin SO)
Fairchild FDS6670A
Component Suppliers
SUPPLIER
Central Semiconductor
Dale-Vishay
Fairchild
IRC
Murata
Nihon
Sanyo
Sumida
Taiyo Yuden
TDK
PHONE
516-435-1110
402-564-3131
408-721-2181
361-992-7900
770-436-1300
847-843-7500
619-661-6835
708-956-0666
800-348-2496
847-390-4373
FAX
516-435-1824
402-563-6296
408-721-1635
361-992-3377
770-436-3636
847-843-2798
619-661-1055
708-956-0702
847-925-0899
847-390-4428
WEBSITE
www.centralsemi.com
www.vishay.com
www.fairchildsemi.com
www.irctt.com
www.murata.com
www.niec.co.jp
www.sanyovideo.com
www.sumida.com
www.t-yuden.com
www.component.tdk.com
Note: Indicate that you are using the MAX1549 when contacting these component suppliers.
Quick Start
Equipment Needed
• 5V to 20V power supply, battery, or notebook AC
adapter
2
• DC bias power supply, 5V at 100mA
• Dummy loads capable of sinking 6A
• Digital multimeters (DMMs)
• 100MHz dual-trace oscilloscope
_______________________________________________________________________________________
MAX1549 Evaluation Kit
Table 3. Jumpers JU3 Functions
(Switching-Frequency Selection)
JU3
TON PIN
FREQUENCY (kHz)
2) Verify that the shunts are installed across pins 1
and 2 of jumper JU1 (ON1 high), pins 1 and 2 of
jumper JU2 (ON2 high), and pins 1 and 2 of JU6
(SKIP high, forced PWM).
1 and 2
Connected to VCC
400
1 and 3
Connected to REF
200
1 and 4
Connected to GND
100
3) Turn on battery power prior to +5V bias power; otherwise, the output UVLO timer times out and the
FAULT latch is set, disabling the regulator outputs
until +5V power is cycled or ON1/ON2 is toggled.
Not
Installed
(Default)
Floating
300
(As Shipped)
4) Verify that the output voltages are V OUT1 = 1.5V,
VOUT2 = 2.5V.
Detailed Description
Note: Do not change the operating frequency without first
recalculating component values. The frequency has a significant effect on preferred inductor value, peak current-limit level,
MOSFET heating, PFM/PWM switchover point, output noise,
efficiency, and other critical parameters.
Jumper Settings
Table 4. Jumpers JU4 and JU5 Functions
(Gate Inputs G0 and G1)
Table 1. Jumper JU1 Functions
(Output Voltage OUT1 Control)
JU1
ON1 PIN
JU4
JU5
OUT1
OUT1 enabled, VOUT1 =
1.5V. OUT1 depends on
gate inputs G0 and G1.
See Table 4.
Not Installed
G0 = GND
Not Installed
G1 = GND
1.50V
(Default)
Installed
G0 = VCC
Not Installed
G1 = GND
1.30V
Not Installed
G0 = GND
Installed
G1 = VCC
1.00V
Installed
G0 = VCC
Installed
G1 = VCC
0.70V
OUT1
1 and 2
(Default)
Connected to VCC.
2 and 3
Connected to GND.
OUT1 shutdown mode
Not
Installed
ON1 must be driven by
an external signal
connected to ON1 pad.
OUT1 operation depends
on the external ON1 signal
levels.
Table 5. Jumper JU6 Functions
(Low-Noise Mode)
Table 2. Jumper JU2 Functions
(Output Voltage OUT2 Control)
JU2
ON2 PIN
OUT2
1 and 2
(Default)
Connected to VCC.
OUT2 enabled, VOUT2 =
2.5V
2 and 3
Connected to GND.
OUT2 shutdown mode
Not
Installed
ON2 must be driven by
an external signal
connected to ON2 pad.
OUT2 operation depends
on the external ON2 signal
levels.
JU6
SKIP PIN
OPERATIONAL
MODE
1 and 2
(Default)
Connected to VCC.
Low-noise mode,
OUT1 and OUT2 are in
forced PWM mode.
2 and 3
Connected to GND.
OUT1 and OUT2 are in
pulse-skipping mode.
_______________________________________________________________________________________
3
Evaluates: MAX1549
Procedure
1) Ensure that the circuit is connected correctly to the
supplies and dummy loads prior to applying any
power.
Evaluates: MAX1549
MAX1549 Evaluation Kit
Evaluating Other Dynamic
Output Voltages (OUT1)
The EV kit output is preset to 0.7V/1.0V/1.3V/1.5V
(OUT1). G0 (JU4) and G1 (JU5) gate inputs select the
OUT1 voltage (see Table 4). However, OUT1 can also
be adjusted between 0.5V and 2.0V by selecting R10–
R14 values. Refer to the MAX1549 data sheet Output
Voltage section for more information.
Evaluating Other Fixed
Output Voltages (OUT2)
The MAX1549 provides a fixed 2.5V output (OUT2)
when FB2 is connected to GND (R20 = open, R21 = 0,
R19 = open) or a fixed 1.8V output when FB2 is con-
4
nected to VCC (R20 = open, R21 = open, R19 = 0).
OUT2 can also be adjusted from 0.5V to 2.7V by using
a resistive voltage-divider formed by R20 and R21 (R19
= open). The MAX1549 regulates FB2 to a fixed reference voltage (0.5V).
The adjusted output voltage is:
VOUT2 = VFB2(1 + R20 / R21) where VFB2 = 0.5V
A 330pF to 1000pF feed-forward bypass capacitor (C26)
reduces duty-cycle jitter and feedback noise.
Refer to the MAX1549 data sheet for selection of output-capacitor and inductor values for different output
voltages.
_______________________________________________________________________________________
MAX1549 Evaluation Kit
Evaluates: MAX1549
VCC
R14
66.5kΩ
1%
R13
150kΩ
1%
VREF
38
R12
487kΩ
1%
39
40
VDD
3
R9
10Ω
VCC
4
C16
470pF
C15
1µF
5
R15
VREF 100kΩ
1%
CSH1
6
29
C9
0.1µF
DH1
VCC
N.C.
LX1
CC1
5
6
8
7
C4
10µF
25V
N1
4
32
31
VIN
20V MAX
C6
OPEN
3
1
5
6
7
DL1
8
R29
OPEN
D1
N.C.
VDD
PGND
G0
BST2
JU4
8
VCC
N.C.
1
1
G1
LX2
9
VCC
SKIP
2
VCC
DL2
10
R26
OPEN
FBLANK
VCC
400kHz
JU3 2
200kHz 3
1
CSH2
CSL2
OPEN
300kΩ 11
VCC
25
VBIAS
+5V
26
C12
2.2µF
22
D3
JU1
VCC
JU2
1
2
1
2 12
C8
0.1µF
19
2
5
6
4
7
ON1
OUT2
R32
OPEN
C21
OPEN
R2
0.015Ω
1%
VOUT2
VOUT2
C3
220µF
4V
D2
N4
C19
OPEN
C27
10µF
6.3V
3
2
C25
OPEN
14
C11
OPEN
15
VCC
C24
OPEN
PG00D2
18
R4
SHORT
(PC TRACE)
R3
SHORT
(PC TRACE)
VCC
R19
OPEN
16
VOUT2
3
13
8
R8
100kΩ
FB2
C7
OPEN
L2
4.7µH
3
2
4
24
C5
10µF
25V
N3
5
6
VIN
BST1
8
7
21
FSEL
PG00D2
GND
3
1
R23
SHORT
(PC TRACE)
20
4
100kHz
C28
10µF
6.3V
VDD
1
R25
R24 OPEN
OPEN
C2
470µF
2.5V
3
G1
R28
100kΩ
C1
OPEN
VOUT1
0.7V TO 1.5V AT 6A
2
1
JU5
VREF
G0
DH2
R27
100kΩ
28
23
C20
OPEN
VOUT1
3
VCC
ILIM2
C18
100pF
R1
0.012Ω
1%
4
27
JU6
7
GND
L1
1.5µH
2
30
U1
MAX1549
ILIM1
VCC
ON2
VIN
BST1
REF
SKIP
ON1
C23
OPEN
R22
SHORT
(PC TRACE)
C17
100pF
R18
100kΩ
1%
VREF
BST1
R5
C10
SHORT
OPEN (PC TRACE)
36
REFIN
R6
SHORT
(PC TRACE)
C22
OPEN
35
N2
R16
100kΩ
1%
R17
VREF 100kΩ
1%
OD3
1
GND
2
N.C.
VREF
C14
0.22µF
CSL1
PGOOD1
33
R
R11
301kΩ
1%
OD2
34
L
C13
470pF
OUT1
OD1
PGOOD1
R10
100kΩ
1%
R7
100kΩ
VOUT1
37
17
R21
0Ω
VOUT2
R20
OPEN
C26
OPEN
ON2
3
Figure 1. MAX1549 EV Kit Schematic
_______________________________________________________________________________________
5
Evaluates: MAX1549
MAX1549 Evaluation Kit
Figure 2. MAX1549 EV Kit Component Placement Guide—Component Side
6
_______________________________________________________________________________________
MAX1549 Evaluation Kit
Evaluates: MAX1549
Figure 3. MAX1549 EV Kit Component Placement Guide—Solder Side
_______________________________________________________________________________________
7
Evaluates: MAX1549
MAX1549 Evaluation Kit
Figure 4. MAX1549 EV Kit PC Board Layout—Ground/Signal Layer 2
8
_______________________________________________________________________________________
MAX1549 Evaluation Kit
Evaluates: MAX1549
Figure 5. MAX1549 EV Kit PC Board Layout—Ground Plane Layer 3
_______________________________________________________________________________________
9
Evaluates: MAX1549
MAX1549 Evaluation Kit
Figure 6. MAX1549 EV Kit PC Board Layout—Component Side
10
______________________________________________________________________________________
MAX1549 Evaluation Kit
Evaluates: MAX1549
Figure 7. MAX1549 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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11
© 2004 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.