MAX8654EVKIT [MAXIM]
Operates from 4.5V to 14V Supply;
| 型号： | MAX8654EVKIT |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Operates from 4.5V to 14V Supply |
| 文件： | 总13页 (文件大小：699K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-0643; Rev 1; 10/08
MAX8654 Evaluation Kit
Evluates:54/MAX68
General Description
Features
o Internal 26mΩ R
o Guaranteed 8A Output Current
MOSFETs
The MAX8654 evaluation kit (EV kit) is a fully assembled
and tested PCB that demonstrates the capabilities of
the MAX8654 integrated 8A step-down regulator. The
EV kit generates a 3.3V output voltage at load currents
up to 8A from a 4.5V to 14V input voltage range. The
MAX8654 switches at 500kHz and provides over 93.4%
efficiency with the supplied components.
DS(ON)
o Adjustable Over-Current Protection, 6A to 12A
o
1ꢀ Output Accuracꢁ Over ꢂoad, ꢂine, and
Temperature
o Operates from 4.5V to 14V Supplꢁ
o Adjustable Output from 0.6V to 0.85 x V
IN
o Soft-Start Reduces Inrush Supplꢁ Current
o 250kHz to 1.2MHz Adjustable Switching or SYNC
Input
o Compatible with Ceramic, Polꢁmer, and
Component Suppliers
Electrolꢁtic Output Capacitors
SUPPꢂIER
PHONE
WEBSITE
o SYNCOUT Sꢁnchronizes 2nd Regulator 180°
Out-of-Phase
Murata Electronics
North America, Inc.
770-436-1300 www.murata-northamerica.com
o 36-Pin 6mm x 6mm TQFN Package
Taiyo Yuden
TDK Corp.
800-348-2496 www.t-yuden.com
Ordering Information
847-803-6000 www.component.tdk.com
PART
TEMP RANGE
IC PACKAGE
TOKO America, Inc. 847-297-0070 www.tokoam.com
36 TQFN
(6mm x 6mm)
Note: Indicate that you are using the MAX8654 when contact-
ing these component suppliers.
MAX8654EVKIT+
0°C to +70°C
+Denotes a lead-free and RoHS-compliant EV kit.
Component Lists
MAX8654 Circuit
DESIGNATION QTY
DESCRIPTION
DESIGNATION QTY
DESCRIPTION
10µF 20%, 16V X5R ceramic
capacitors (1206)
Taiyo Yuden EMK316BJ106M
1000pF, 50V C0G ceramic
capacitor (0402)
Murata GRM1555C1H1D2TADI
C1A, C1B, C1C
3
1
2
1
3
1
1
C8
C9
1
1
1
1
1
2
0
1µF 10%, 6.3V X5R ceramic
capacitor (0402)
Murata GRM155R60J105K
4.7µF 10%, 16V X5R ceramic
capacitor (0603)
Murata GRM21BR61C475K
C2
0.01µF 10%, 50V X7R ceramic
capacitors (0402)
Murata GRM155R71H103K
0.22µF,16V Y5R ceramic capacitor
(0402)
Taiyo Yuden EMK105BJ224MV-F
C3, C11
C10
0.22µF 20%, 16V X7R ceramic
capacitor (0603)
TDK C1608X7R1C224M
470pF 10%, 50V X7R ceramic
capacitor (0402)
Murata GRM155R71H471K
C4
C12
22µF 20%, 6.3V X5R ceramic
capacitors (1206)
TDK C3216X5R0J226M
0.1µF 10%, 10V X7R ceramic
capacitor (0402)
Murata GRM155R61A104K
C5A, C5B, C5C
C13
6800pF 10%, 50V X7R ceramic
capacitor (0402)
Murata GRM155R71H682KA88
0.22µF 20%, 50V X5R ceramic
capacitors (0805)
Taiyo Yuden UMK212BJ224M
C6
C7
C14, C15
C16
0.022µF, 10V X7R ceramic
capacitor (0402)
Not installed, 0.01µF 10%, 25V X7R
ceramic capacitor (0402)
Murata GRM155R71C223CKA0I
Murata GRM155R71E103K
________________________________________________________________ Maxim Integrated Products
1
For pricing, deliverꢁ, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
MAX8654 Evaluation Kit
MAX8688 Circuit—Not Installed
Component Lists (continued)
DESIGNATION QTY
DESCRIPTION
MAX8654 Circuit
R201, R204,
R206, R208,
R209, R214
DESIGNATION QTY
DESCRIPTION
0
Resistors, open
JP1–JP7,
0
Not installed
JP9–JP13
R202
R203
0
0
0Ω resistor (0402)
JU1, JU2, JU4
JU3
3
1
2-pin headers
3-pin header
1kΩ 1% resistor (0402), open
R205, R207,
R210
0
33kΩ 1% resistors (0402), open
1µH, 7.9mΩ, 12A inductor (7.4mm x
6.7mm x 3mm)
TOKO FDV0630-1R0M
L1
1
R211
0
0
0
0
0
0
909Ω 5% resistor (0603), open
100kΩ 1% resistor (0402), open
10kΩ 1% resistor (0402), open
100Ω 1% resistors (0402), open
MAX8688+, open
R213
R215
R1, R2, R10
3
1
1
1
1
1
1
2
1
100kΩ 1% resistors (0402), lead free
1.5kΩ 1% resistor (0402), lead free
332Ω 1% resistor (0402), lead free
15Ω 5% resistor (0402), lead free
475Ω 1% resistor (0402), lead free
75kΩ 1% resistor (0402), lead free
2.2Ω 1% resistor (1206), lead free
1kΩ 1% resistors (0402), lead free
10Ω 1% resistor (0402), lead free
R3
R4
R216, R217
U201
R5
U202
AT24C01A-10TSU-1.8, open
R6
R7
Quick Start
R8
R9, R11
R12
Recommended Equipment
Before beginning, the following equipment is needed:
8A step-down regulator
Maxim MAX8654ETX+
•
•
•
•
Up to 12V at +3A DC power supply or battery
Digital multimeter (DMM)
Up to 8A load
U1
1
—
—
3
1
Shunts
PCB: MAX8654 Evaluation Kit+
Ammeter (optional)
Procedure
Evluates:54/MAX68
MAX8688 Circuit—Not Installed
The MAX8654 EV kit is fully assembled and tested.
Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all con-
nections are made.
DESIGNATION QTY
DESCRIPTION
C201, C202,
C203, C205,
C206, C207
100nF 10%, 50V X7R ceramic
capacitors (0603), open
Murata GRM188R71H104K
1µF 10%, 10V X5R ceramic
capacitor (0603), open
0
0
1) Preset the DC power supply to 12V. Turn off the
power supply.
C204
2) Ensure that there is a shunt on JU1 and JU2.
3) Ensure that there is a shunt on pins 1-2 of JU3.
Murata GRM188R61A105K
2.2µF 10%, 10V X5R ceramic
capacitor (0603), open
C208
C209
C210
0
0
0
4) Connect the positive lead of the power supply to the
VIN pad and connect the negative lead of the
power supply to the GND pad on the EV kit.
Taiyo Yuden LMK107BJ225K
Ceramic capacitor, open
0.47µF 10%, 10V X5R ceramic
capacitor (0603), open
5) Connect the positive lead of the DMM to the VOUT
pad and connect the negative lead of the DMM to
the GND pad on the EV kit.
Murata GRM188R61A474K
3.3V 350mW zener diode (SOT23),
open
6) Turn on the power supply.
D1
0
7) Verify that the voltage at VOUT is approximately
3.3V.
Central Semiconductor CMPZ4620
JP201
0
0
0
4-pin header, open
3-pin header, open
100kΩ resistor, open
8) Connect the load between VOUT and GND.
JP202, JP203,
JP204
9) Verify that the voltage at VOUT is approximately
3.3V.
R19
2
_______________________________________________________________________________________
MAX8654 Evaluation Kit
Evluates:54/MAX68
Soft-Start and REFIN
The MAX8654 utilizes an adjustable soft-start function
to limit inrush current during startup. An 8µA (typ) cur-
rent source charges an external capacitor (C3) con-
nected to SS to increase the capacitor voltage in a con-
trolled manner. The soft-start time is adjusted by the
value of the external capacitor from SS to GND. The
required capacitance value is determined as:
Detailed Description of Hardware
Evaluating Other Switching
Frequencies (FREQ)
The switching frequency in fixed-frequency PWM oper-
ation is resistor-programmable from 250kHz to 1.2MHz.
Set the switching frequency of the IC with a resistor
(R
) from FREQ to GND. R
is calculated as:
FREQ
FREQ
8μA×t
ss
⎛
⎞
1
C =
R
= 52.36×
− 0.05μs kΩ
FREQ
⎜
⎟
0.6V
f
⎝
⎠
s
where t is the required soft-start time in seconds.
SS
where f is the desired switching frequency in megahertz.
S
The MAX8654 also features an external reference input
(REFIN). The IC regulates FB to the voltage applied to
REFIN. The internal soft-start is not available when
using an external reference. A method of soft-start
when using an external reference is shown in the
MAX8654 data sheet. Connect REFIN to SS to use the
internal 0.6V reference (jumper JU3).
Undervoltage Lockout (UVLO)
The UVLO circuitry inhibits switching when V or V
IN
VDL
is below 4.4V (V , V
rising) or V is below 3.1V
IN
VDL
VL
(V rising). Once these voltages are above the thresh-
VL
olds, UVLO clears and the soft-start function activates.
A 100mV hysteresis is built in for glitch immunity.
Power Good (PWRGD)
PWRGD is an open-drain output that goes high imped-
ance once the soft-start ramp has concluded, provided
Jumper Settings
Jumper JU1 Function
Drive EN high by placing a shunt on JU1 to turn on the
IC. To shut down the IC and reduce quiescent current
to 10µA (typ), remove the shunt on JU1. During shut-
down, the outputs of the MAX8654 are high impedance.
V
and V
are above 0.54V. PWRGD pulls low
FB
REFIN
when V falls below 0.54V for at least 50µs or V
FB
REFIN
is less than 0.54V. PWRGD is low during shutdown.
SYNC and SYNCOUT
The MAX8654 features a SYNC function that allows the
switching frequency to be synchronized to any external
clock frequency that is higher than the internal clock
frequency. Drive SYNC with a square wave at the
desired synchronization frequency. A rising edge on
SYNC triggers the internal SYNC circuitry. Connect
SYNC to GND to disable the function and operate with
the internal oscillator. The SYNCOUT output generates
a clock signal that is 180° out-of-phase with its internal
oscillator, or the signal applied to SYNC. This allows for
another MAX8654 to be synchronized 180° out-of-
phase to reduce the input ripple current.
Jumper JU2 Function
Place a shunt on jumper JU2 to connect SYNC to GND.
Jumper JU3 Function
Place a shunt on pins 1-2 of JU3 to connect the REFIN
pin to the SS pin. When using an external reference,
place a shunt on pins 2-3 of jumper JU3.
Evaluating the MAX8688
The MAX8688 is a fully digital power-supply manager
that can be tested in conjunction with the MAX8654.
Samples of the MAX8688 IC can be ordered from
Maxim. To test the MAX8688, populate it with its circuit-
ry, as shown by the schematic or in the component list.
Also, place a shunt on pins 2-3 of JU3. For further infor-
mation, refer to the MAX8688 IC data sheet.
_______________________________________________________________________________________
3
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 1a. MAX8654 EV Kit Schematic (Sheet 1 of 2)
4
_______________________________________________________________________________________
MAX8654 Evaluation Kit
Evluates:54/MAX68
AM6X8
Figure 1b. MAX8654 EV Kit Schematic (Sheet 2 of 2)
_______________________________________________________________________________________
5
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 2. MAX8654 EV Kit Component Placement Guide—Component Side
6
_______________________________________________________________________________________
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 3. MAX8654 EV Kit PCB Layout—Component Side
_______________________________________________________________________________________
7
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 4. MAX8654 EV Kit PCB Layout—Inner Layer 1
8
_______________________________________________________________________________________
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 5. MAX8654 EV Kit PCB Layout—Inner Layer 2
_______________________________________________________________________________________
9
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 6. MAX8654 EV Kit PCB Layout—Inner Layer 3
10 ______________________________________________________________________________________
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 7. MAX8654 EV Kit PCB Layout—Inner Layer 4
______________________________________________________________________________________ 11
MAX8654 Evaluation Kit
Evluates:54/MAX68
Figure 8. MAX8654 EV Kit PCB Layout—Solder Side
12 ______________________________________________________________________________________
MAX8654 Evaluation Kit
Evluates:54/MAX68
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
0
1
5/07
Initial release
—
10/08
Change in compensation components (C6, C7, C8, R5, and R6)
1, 2, 4
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 ____________________ 13
© 2008 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
相关型号：
©2020 ICPDF网 联系我们和版权申明