MAX8821EVKIT [MAXIM]
Fully Assembled and Tested;
| 型号： | MAX8821EVKIT |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Fully Assembled and Tested |
| 文件： | 总14页 (文件大小：231K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-4085; Rev 0; 4/08
MAX8821 Evaluation Kit
Evluates:MAX821
General Description
Features
♦ Windows 2000/XP/Vista (32-Bit)-Compatible
The MAX8821 evaluation kit (EV kit) is a fully assembled
and tested circuit for evaluating the MAX8821 white
LED charge pump with a mono Class D audio amplifier
and dual LDOs. The MAX8821 EV kit operates from a
2.7V to 5.5V input supply range and is controlled by an
I2C interface. The MAX8821 features a high-efficiency,
adaptive-mode inverting charge pump that drives up to
six LEDs with constant current for uniform brightness.
Software
♦ CMAXQBUSB+ Interface Board with USB PC
Connection (Cable Included)
♦ Proven PCB Layout
♦ Fully Assembled and Tested
♦ White LED Inverting Charge Pump
Independent Adaptive Current Regulators for
Each LED
®
®
The EV kit also includes Windows 2000/XP/Vista
-compatible software that provides a simple graphical
user interface (GUI) for exercising the features of the
MAX8821. The EV kit software features an I2C interface
to control the LED current, ramp-up/ramp-down time,
and blink on/off-time. An internal temperature derating
function reduces the current above +40°C to protect
the LEDs.
Six Low-Dropout Current Regulators
Flexible I2C Dimming Control for Each LED
Ramp Up/Down Current Control for Each LED
Low 70µA (typ) Quiescent Current
T Derating Function Protects LEDs
A
♦ Mono 2W Class D Loudspeaker Amplifier
85% Efficiency (R = 8Ω, P
= 600mW)
L
OUT
The MAX8821 also features a mono Class D audio
amplifier with adjustable gain, through the I2C interface,
from -3dB to +24dB in ten 3dB steps. The I2C control
interface selects the audio amplifier fixed-frequency
mode or spread-spectrum mode, in addition to select-
ing individual LDO output voltages.
Low 0.05% THD+N at 1kHz
High 65dB PSRR at 1kHz
Fully Differential Inputs
-3dB to +24dB Gain Settings in 3dB Steps
Integrated Click-and-Pop Suppression
Low Quiescent Current
♦ Dual Low-Noise LDO
45µV
Output Noise, 73dB PSRR
RMS
Flexible I2C-Controlled Output Voltages
200mA and 300mA Output Current Drive
Ordering Information
PART
TYPE
MAX8821EVKIT+
EV Kit
+Denotes lead-free and RoHS compliant.
Component List
DESIGNATION QTY
DESCRIPTION
DESIGNATION QTY
DESCRIPTION
1µF 10ꢀ, 6.3V X5R ceramic
capacitors (0402)
TDK C1005X5R0J105K
Murata GRM155R60J105K
Taiyo Yuden LMK105BJ105K
33,000pF 10ꢀ, 10V X7R ceramic
capacitors (0402)
Murata GRM155R71A333K
Taiyo Yuden EMK105B7333K
KEMET C0402C333K8RACTU
C1, C2, C3, C6,
7
C13, C15
2
C8, C9, C11
0.1µF 10ꢀ, 10V X5R ceramic
capacitors (0402)
TDK C1005X5R1C104K
Murata GRM155R61A104K
Taiyo Yuden LMK105BJ104K
68,000pF 10ꢀ, 10V X5R ceramic
capacitors (0402)
TDK C1005X5R1C683K
Murata GRM155R61A683K
C14, C16
C17
2
1
C4, C12
2
3
0.15µF 10ꢀ, 6.3V X7R ceramic
capacitor (0402)
TDK C1005X5R0J154K
AVX 04026D154KAT2A
2.2µF 20ꢀ, 6.3V X5R ceramic
capacitors (0402)
Taiyo Yuden JMK105BJ225M
C5, C7, C10
Windows and Windows Vista are registered trademarks of Microsoft Corp.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX8821 Evaluation Kit
Component List (continued)
DESIGNATION QTY
DESCRIPTION
White LEDs
Nichia NSCW215T
DESIGNATION QTY
DESCRIPTION
5-pin headers
D1–D6
D7
6
1
1
1 x 36-pin header, 0.1in centers
(comes in 1 x 36-pin strips, cut to fit)
Sullins PEC36SAAN
JU6, JU7
L1, L2
2
2
Lumex RGB LED
SML-LX3632SISUGSBC
Digi-Key S1012E-36-ND
2 x 10 right-angle receptacle
Methode M65S-R220-11-01W
15µH inductors
TOKO A916CY-150M
(D63CB series)
J1
2-pin headers
1 x 36-pin header, 0.1in centers
(comes in 1 x 36-pin strips,
cut to fit)
Sullins PEC36SAAN
Digi-Key S1012E-36-ND
2.21kΩ 1ꢀ resistors (0402)
lead-free
R1, R2
R3, R4
2
2
JU1, JU2, JU3
3
2
22.1Ω 1ꢀ resistors (0402)
lead-free
White LED charge pump
(28 thin QFN-EP*)
Maxim MAX8821ETI+
3-pin headers
U1
—
1
1 x 36-pin header, 0.1in centers
(comes in 1 x 36-pin strips,
cut to fit)
Sullins PEC36SAAN
Digi-Key S1012E-36-ND
CMAXQUSB+ interface module
including USB high-speed A-to-B
cables, 6ft
JU4, JU5
Evluates:MAX821
1
1
—
MAX8821EVKIT+ PCB
*EP = Exposed pad.
Component Suppliers
SUPPLIER
PHONE
WEBSITE
AVX Corp.
843-448-9411
864-963-6300
520-877-8456
708-867-6777
770-436-1300
248-349-9800
408-573-4150
847-803-6100
408-432-8281
402-563-6866
www.avxcorp.com
www.kemet.com
KEMET Corp.
Lumex, Inc.
www.lumex.com
Methode Electronics
Murata Electronics North America, Inc.
Nichia Corp.
www.methode.com
www.murata-northamerica.com
www.nichia.com
Taiyo Yuden
www.t-yuden.com
www.component.tdk.com
www.tokoam.com
TDK Corp.
TOKO America, Inc
Vishay
www.vishay.com
Note: Indicate that you are using the MAX8821 when contacting these component suppliers.
MAX8821 EV Kit Software Files
FILE
INSTALL.EXE
MAX8821.EXE
FTD2XX.INF
DESCRIPTION
Installs the EV kit files on your computer
Application program
USB device driver file
UNINST.INI
Uninstalls the EV kit software
USB driver installation help file
USB_Driver_Help.PDF
2
_______________________________________________________________________________________
MAX8821 Evaluation Kit
Evluates:MAX821
you do not see a window that is similar to the one
described above after 30s, remove the USB cable
from the board and reconnect it. Administrator privi-
leges are required to install the USB device driver
on Windows.
Quick Start
Recommended Equipment
• MAX8821 EV kit
• 2.5V to 5.5V power supply capable of delivering 2A
• Two digital multimeters (DMM1, DMM2)
• Audio source (i.e., CD player, MP3 player, etc.)
• 4Ω/8Ω speaker
4) Follow the directions of the Add New Hardware
Wizard to install the USB device driver. Choose the
Search for the best driver for your device option.
Specify the location of the device driver to be
C:\Program Files\MAX8821 (default installation
directory) using the Browse button. During device
driver installation, Windows may show a warning mes-
sage indicating the device driver that Maxim uses
does not contain a digital signature. This is not an
error condition and it is safe to proceed with installa-
tion. Refer to the document USB_Driver_Help.PDF for
additional information.
• A user-supplied Windows 2000/XP/Vista PC with a
spare USB port
• CMAXQUSB+ command module (USB cable included)
Note: In the following sections, software-related items
are identified by bolding. Text in bold refers to items
directly from the MAX8821 EV kit software. Text in bold
and underlined refers to items from the Windows
2000/XP/Vista operating system.
5) Preset the power supply to 3.6V. Turn off the power
supply. Do not turn on the power supply until all
connections are complete.
Procedure
The MAX8821 EV kit is a fully assembled and tested
surface-mount board. Follow the Power Up section to
verify board operation and Power Down section to safe-
ly power down the EV kit.
6) On the CMAXQUSB command module, ensure that
the shunt on jumper JU1 is in the 3.3V position.
7) Verify that JU1 (MAX8821 EV kit) is installed.
Power Up
Reference Figure 1 and the power-up procedure below
to properly verify the MAX8821 EV kit.
8) Verify that JU4 and JU5 (MAX8821 EV kit) have
shunts installed across pins 1 and 2.
9) Verify that the center pin of JU6 is connected to
PCB label B.
1) Visit www.maxim-ic.com/evkitsoftware to download
the latest version of the EV kit software,
8821Rxx.ZIP. Save the EV kit software to a tempo-
rary folder and uncompress the ZIP file.
10) Verify that the center pin of JU7 is connected to
PCB label R.
11) Carefully connect the boards by aligning the 20-pin
connector of the MAX8821 EV kit with the 20-pin
header of the CMAXQUSB interface board. Gently
press them together.
2) Install the EV kit software on your computer by run-
ning the INSTALL.EXE program inside the temporary
folder. The program files are copied and icons are
created in the Windows Start | Programs menu.
12) Connect the positive lead of the power supply to
VBATT+ and the negative lead to VBATT-.
3) Connect the USB cable from the PC to the EV kit
board. A Building Driver Database window pops
up in addition to a New Hardware Found message
when installing the USB driver for the first time. If
13) Observe correct speaker polarity. Connect the
speaker across the SPK+ and SPK- test points.
_______________________________________________________________________________________
3
MAX8821 Evaluation Kit
VERIFY
SHUNT
VERIFY RED
LED LIGHT
VERIFY BLUE
LED LIGHT
POWER SUPPLY
+2.7V TO +5.5V
-
+
VERIFY SHUNT
D7
R
VERIFY SHUNT
JU7
JU1
JU5
1
2
3
B
W
W
D6
D5
D4
D3
D2
D1
VERIFY SHUNTS
ARE NOT INSTALLED
G
R
AIN+
AIN-
+
-
JU2
JU3
JU6
B
DIFFERENTIAL
AUDIO INPUT
G
MAX8821
EV KIT+
VERIFY SHUNT
JU4
VERIFY WHITE
LED LIGHT
(D1–D4)
1
2 3
GND
Evluates:MAX821
-
+
VERIFY SOUND FROM
4Ω/8Ω SPEAKER
VERIFY SHUNT
J1
VOLTMETER
(DMM2)
+
+
-
CONNECT 20-PIN
RECEPTACLE TO
CMAXQUSB+ (P3)
VOLTMETER
(DMM1)
-
Figure 1. Test Procedure Setup for MAX8821 EV Kit
14) Observe correct audio source polarity. Connect
the audio source to AIN+ and AIN-. Refer to the
MAX8821 data sheet for more information about dif-
ferential audio signals, single-ended audio signals,
input capacitors (C1, C2 in Figure 5), and the com-
mon-mode bias voltage range.
16) Connect the positive lead of DMM2 to LDO2 and
the negative lead to GND.
17) Turn on the power supply.
18) Turn on the audio source.
19) Start the MAX8821 EV kit software by opening its icon
at Start | Programs | MAX8821 EVALUATION KIT.
15) Connect the positive lead of DMM1 to LDO1 and
the negative lead to GND.
4
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MAX8821 Evaluation Kit
Evluates:MAX821
Figure 2. Status: EV Kit Operational
20) Normal device operation is verified when EV Kit
Operational is displayed by the Status indicator as
shown in Figure 2. If the status indicator displays an
error, see the Troubleshooting section.
26) Select the LDO2 output voltage to be 3.3V.
27) Select the corresponding Enable box to enable LDO2.
28) Verify the voltage read by DMM2 is 3.3V.
29) Select the corresponding Active Pull Down and
21) Select the LDO1 output voltage to be 3.2V.
disable LDO2.
22) Select the corresponding Enable box to enable
30) Verify the voltage read by DMM2 is 0V.
31) Set LED1–LED6 to the 25.6mA setting.
LDO1.
23) Verify the voltage read by DMM1 is 3.2V.
32) Enable the ramp function for LED1–LED4 by select-
24) Select the corresponding Active Pull Down and
ing the corresponding Ramp boxes.
disable LDO1.
33) Select LED1 to a ramp-up and ramp-down time of
262ms.
25) Verify the voltage read by DMM1 is 0V.
_______________________________________________________________________________________
5
MAX8821 Evaluation Kit
34) Select LED2 to a ramp-up and ramp-down time of
524ms.
43) Verify that D7 emits both red and blue light.
44) Verify that D7 emits the blue light for a longer time
than the red light.
35) Select LED3 to a ramp-up and ramp-down time of
1048ms.
45) Select the audio amplifier to have a +3dB gain.
36) Select LED4 to a ramp-up and ramp-down time of
2097ms.
46) Enable the audio amplifier by selecting the corre-
sponding Enable box.
37) Enable LED1–LED4 by selecting the corresponding
47) Verify that sound is coming from the speaker.
Enable boxes.
48) Set the audio gain to +12dB and verify that the
volume has increased.
38) Verify that D1–D4 emit white light and display a
sequenced ramp-up time with LED1 as the fastest
ramp-up time and LED4 as the slowest.
Power Down
When evaluation of the MAX8821 EV kit is completed, use
the following steps to power down the MAX8821 EV kit:
39) Enable the blink function for LED5 and LED6 by
selecting the corresponding Blink boxes.
1) Turn off the power supply and audio source.
40) Select LED5 to a blink ON time of 512ms and blink
OFF time of 512ms.
2) Disconnect the power supply, audio source, speak-
er, DMMs, and test leads from the MAX8821 EV kit.
41) Select LED6 to a blink ON time of 66ms and blink
OFF time of 4194ms.
3) Disconnect the MAX8821 EV kit from the
CMAXQUSB+ command module.
42) Enable LED5 and LED6 by selecting the corre-
Evluates:MAX821
sponding Enable boxes.
Table 1. Jumper Settings
JUMPER
FUNCTION
Shorts VBATT+ (2.7V to 5.5V) to the anodes of all LEDs (D1–D7). Short JU1 to connect all LEDs to the power
supply for normal operation. Open JU1 to disconnect all LEDs from the power supply.
JU1
JU2
JU3
Short JU2 to directly apply a common-mode audio signal (0.5V to V
- 1.2V) to the IC’s noninverting input. Open
IN3
JU2 to remove the DC bias from the audio input with the AC-coupling capacitor (C2).
Short JU3 to directly apply a common-mode audio signal (0.5V to V - 1.2V) to the IC’s inverting input. Open JU3
IN3
to remove the DC bias from the audio input with the AC-coupling capacitor (C1).
Connect pins 1 and 2 of JU4 to apply a differential signal to AIN- . Connect pins 2 and 3 to connect AIN- to ground
to apply a single-ended audio signal to AIN+. (Note: JU2 must be open when a single-ended audio signal is
applied to AIN+.)
JU4
JU5
2
Connect pins 2 and 3 to connect V (1.5V to 5.5V), the I C power supply, to VBATT+ (2.7V to 5.5V). Connect pins
DD
2
1 and 2 to connect V (1.5V to 5.5V) to the I C interface supply voltage with J1.
DD
Connect the center pin of JU6 to the pin labeled W to connect a white LED (D5) to the internal current regulator.
Connect the center pin of JU6 to the pin labeled R to connect the red LED in the RGB diode (D7) to the internal
current regulator.
JU6
JU7
Connect the center pin of JU6 to the pin labeled B to connect the blue LED in the RGB diode (D7) to the internal
current regulator.
Connect the center pin of JU6 to the pin labeled G to connect the green LED in the RGB diode (D7) to the internal
current regulator.
Connect the center pin of JU7 to the pin labeled W to connect a white LED (D6) to the internal current regulator.
Connect the center pin of JU7 to the pin labeled R to connect the red LED in the RGB diode (D7) to the internal
current regulator.
Connect the center pin of JU7 to the pin labeled B to connect the blue LED in the RGB diode (D7) to the internal
current regulator.
Connect the center pin of JU7 to the pin labeled G to connect the green LED in the RGB diode (D7) to the internal
current regulator.
6
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MAX8821 Evaluation Kit
Evluates:MAX821
Figure 3. Status: Interface Module Not Connected
2) Verify that the MAX8821 EV kit is connected to the
CMAXQUSB+ by J1.
Troubleshooting
If the status indicator shows Interface Module Not
Connected as shown in Figure 3 verify that the USB
cable is plugged into the original port. If the USB cable
is plugged into a different port, the interface module
drivers need to be reinstalled. Refer to the HELP.PDF
found at Start | Programs | MAX8821 EVALUATION
KIT for further details.
3) Verify that JU1 on the CMAXQUSB+ command
module selects a 3.3V logic level.
4) Verify that shunts are installed for J3 and J2 on the
CMAXQUSB+ command module.
5) On the MAX8821 EV kit, verify that pins 1 and 2 of
JU5 are connected.
If the status indicator shows EV Kit Not Found as
shown in Figure 4 check the following:
1) Verify that the power supply is properly connected
and is within the 2.7V to 5.5V range.
_______________________________________________________________________________________
7
MAX8821 Evaluation Kit
Evluates:MAX821
Figure 4. Status: EV Kit Not Found
8
_______________________________________________________________________________________
MAX8821 Evaluation Kit
Evluates:MAX821
Failing to comply with these timing constraints results in
the LED_ not reaching the programmed current during
Detailed Description
The MAX8821 EV kit features LED display backlighting,
an audio loudspeaker amplifier, and dual LDOs for
camera functions. The MAX8821 includes soft-start,
thermal shutdown, open-circuit and short-circuit protec-
tions for the white LEDs, audio amplifier, and two LDOs.
the ON time, and the I
_ current not returning to 0mA
LED
during the off time. Refer to the equations found in the
Combining Blink Timer and Ramp Function section of
the MAX8821 IC data sheet.
LED Short and Open-Circuit Protection
If any LED fails as an open circuit, the corresponding
LED_ is internally connected to ground and the charge
pump is enabled. To disable the corresponding current
regulator, short any unused LED_ to VBATT+. The
MAX8821 contains special circuitry to detect this con-
dition and disables the corresponding current regulator
to avoid wasting battery power.
LED Charge Pump
The MAX8821 features an inverting charge pump and
six current regulators capable of 25.6mA each to drive
six LEDs. The current regulators are matched to within
1ꢀ (typ), providing uniform white LED brightness for
LCD backlight applications. To maximize efficiency, the
current regulators operate with as little as 0.15V voltage
drop. Individual white LED current regulators conduct
current to GND or NEG to extend usable battery life. In
the case of mismatched forward voltage of white LEDs,
only the white LEDs requiring higher voltage are
switched to direct current to NEG instead of GND, fur-
ther raising efficiency and reducing battery current
drain. The on-chip ambient temperature derating func-
tion safely allows bright 25.6mA full-scale output cur-
rent while automatically reducing current gradually
above +40°C in accordance with popular LED ratings.
Temperature Derating
The MAX8821 contains a derating function that auto-
matically limits the LED current at high temperatures in
accordance with the recommended derating curve of
popular white LEDs. The derating function enables the
safe usage of higher LED current at room temperature,
thus reducing the number of LEDs required to backlight
the display. The derating circuit reduces the LED cur-
rent above +40°C at approximately 1.67ꢀ/°C. The tem-
perature derating function is enabled/disabled using the
MAX8821 EV kit software and by default is disabled.
Ramp-Up and Ramp-Down Function
The LED drivers in the MAX8821 provide ramp-up, and
ramp-down of LED current for smooth transitions
between different brightness settings. A controlled ramp
is used when the LED current level is changed, when
the LEDs are enabled, and when the LEDs are disabled.
Audio Amplifier
The audio amplifier in the MAX8821 is a 2W Class D
loudspeaker amplifier. The amplifier features a pro-
grammable gain control through the MAX8821 EV kit
software and can be set from -3dB to +24dB.
The LED currents ramp up and down smoothly on a
pseudo-log scaling of the LED current sources. Each
LED source has an individual ramp control making it
possible to ramp different LEDs at different rates.
The amplifier operates from a single 2.7V to 5.5V sup-
ply and features an internally generated common-mode
bias voltage of V /2 referenced to ground.
IN3
A unique filterless modulation scheme and spread-
spectrum mode create a compact, flexible, low-noise,
efficient audio power amplifier while occupying minimal
board space. The differential input architecture
reduces common-mode noise pickup with or without
the use of input-coupling capacitors. The MAX8821
audio amplifier can also be configured as a single-
ended input amplifier. The input capacitor C2 is
required for single-ended input applications.
Blink Timer
The current regulators for LED5 and LED6 feature a
blink function. The OFF and ON time for LED5 and
LED6 can be set using the MAX8821 EV kit software.
Combining Blink Timer and Ramp Function
To combine the ramp function together with the blink
timer for LED5 and/or LED6, special timing considera-
tions need to be fulfilled. It is recommended to keep
the ramp-up timer shorter than the ON blink timer and
the ramp-down timer shorter than the OFF timer.
_______________________________________________________________________________________
9
MAX8821 Evaluation Kit
Audio Input Filter
The fully differential amplifier inputs can be biased at
voltages other than midsupply. The common-mode
feedback circuit adjusts for input bias, ensuring the out-
puts are still biased at midsupply. Input capacitors (C2,
C1 in Figure 5) are not required as long as the com-
mon-mode input voltage is within the specified range
listed in the Electrical Characteristics table found in the
MAX8821 IC data sheet. If the input capacitors are
Thermal Shutdown
The MAX8821 includes a thermal-limit circuit that shuts
down the IC at a junction temperature of approximately
+160°C. The IC turns on after it cools by approximately
20°C.
Shutdown Mode
The MAX8821 can be put into two different shutdown
modes. The first shutdown mode is achieved by driving
V
DD
low. In this mode, the I2C interface becomes dis-
used in conjunction with on-chip R , they form a high-
INT
abled. The second shutdown is a lower power mode.
To enter the low-power mode, disable LED_, audio
amplifier, or LDOs through the MAX8821 EV kit soft-
ware. In low-power mode, the I2C interface is still
active.
pass filter that removes the DC bias from an incoming
signal. The AC-coupling capacitor allows the amplifier
to bias the signal to an optimum DC level.
LDO1 and LDO2
The linear regulators are designed for low-dropout and
low quiescent current to maximize battery life. Both
LDOs are controlled through the I2C interface, minimiz-
ing the number of control lines to the MAX8821. I2C con-
trols the output voltages, and the enable/disable state for
both LDO1 and LDO2. At startup, the LDOs are off but
are preset to 1.2V for LDO1 and 1.5V for LDO2.
2
I C Address
The MAX8821 acts as a slave transmitter/receiver. The
slave address of the MAX8821 is preset to 1001110X,
where X is the R/W bit. The address 0x9C is designated
for write operations and 0x9D for read operations. The
I2C register is reset back to the default value when
Evluates:MAX821
either V drops below the UVLO threshold, or V
IN
is
DD
driven low.
10 ______________________________________________________________________________________
MAX8821 Evaluation Kit
Evluates:MAX821
C8
C9
1μF
1μF
25
C1P
IN1
23
C1N
24
C2P
22
C2N
VBATT+
VBATT+
26
27
8
21
VBATT+
VBATT-
GND
NEG
VNEG
JU1
C7
2.2μF
C6
1μF
PGND1
IN2
15
16
17
18
D1
D2
D3
D4
LED1
LED2
LED3
LED4
D7
G
C3
1μF
R
B
D6
5
PGND2
IN3
R
B
U1
28
13
W
G
C5
2.2μF
G
JU7
MAX8821+
AGND
R
B
D5
JU6
19
20
W
LED5
LED6
14
2
REF
C4
0.1μF
J1
VI2C
HEADER
20-PIN
10
LDO1
LDO1
J1-1
J1-2
C10
2.2μF
CMREF
C12
0.1μF
SDA
SCL
J1-3
J1-5
J1-7
J1-9
J1-4
J1-6
VBATT+
J1-8
1
JU5
VDD
J1-10
R2
2.21kΩ
9
J1-11 J1-12
J1-13 J1-14
J1-15 J1-16
J1-17 J1-18
J1-19 J1-20
LDO2
LDO2
R1
VI2C
C11
1μF
12
11
2.21kΩ
SDA
SDA
SDA
SCL
SCL
SCL
JU2
SPK+
C2
L1
1μF
15μH
7
6
3
4
SPK+
SPK-
FSPK+
FSPK-
AIN+
AIN-
AIN+
AIN+
C13
33,000pF
C14
68,000pF
C1
1μF
C17
0.15μF
R3
22.1Ω
JU4
L2
15μH
JU3
C15
33,000pF
C16
68,000pF
EP
R4
22.1Ω
SPK-
Figure 5. MAX8821 EV Kit Schematic
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MAX8821 Evaluation Kit
Evluates:MAX821
Figure 6. MAX8821 EV Kit Component Placement Guide—Component Side
12 ______________________________________________________________________________________
MAX8821 Evaluation Kit
Evluates:MAX821
Figure 7. MAX8821 EV Kit PCB Layout—Component Side
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MAX8821 Evaluation Kit
Evluates:MAX821
Figure 8. MAX8821 EV Kit PCB 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.
14 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2008 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
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