Texas Instruments TPA6138A2 EVM User manual

User's Guide
SLOU305A–November 2010–Revised January 2011
TPA6138A2 EVM
Contents
1 Introduction .................................................................................................................. 1
2 Operation ..................................................................................................................... 3
3 Reference .................................................................................................................... 4
4 TPA6138A2EVM Bill of Materials ......................................................................................... 6
List of Figures
1 TPA6138EVM Top View ................................................................................................... 1
2 TPA6138EVM Bottom View ............................................................................................... 2
3 Top Layer .................................................................................................................... 5
4 Bottom Layer ................................................................................................................ 5
List of Tables
1 TPA6138A2EVM Bill of Materials......................................................................................... 6
1 Introduction
This section provides an overview of the Texas Instruments (TI) TPA6138A2 DirectPath™ stereo
headphone amplifier evaluation module (EVM). It includes a brief description of the module and a list of
EVM specifications.
Figure 1. TPA6138EVM Top View
DirectPath is a trademark of Texas Instruments.
1
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Introduction www.ti.com
Figure 2. TPA6138EVM Bottom View
1.1 Description
The TPA6138A2 is a DirectPath™ stereo headphone amplifier capable of delivering 25 mW/Ch into 32 Ω
and requires no output DC blocking capacitors.
The TPA6138A2 EVM is a complete, stand-alone audio board. It contains the TPA6138A2 TSSOP
DirectPath™ stereo headphone amplifier.
1.2 EVM Specifications
Supply voltage range, VDD 3 V to 3.6 V
Supply current, IDD 0.5 A, maximum
Continuous output power, PO, VDD = 3.3 V, 32 Ω, THD+N < 1 % 20 mW
2TPA6138A2 EVM SLOU305A–November 2010–Revised January 2011
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www.ti.com Operation
2 Operation
This section describes how to operate the TPA6138A2EVM.
2.1 Quick-Start List for Stand-Alone Operation
Use the following steps when operating the TPA6138A2EVM stand alone or when connecting the EVM
into an existing circuit.
2.1.1 Power and Ground
1. Verify that the external power sources are set to OFF.
2. Set the power supply voltage between 3 V and 3.6 V. When connecting the power supply to the EVM,
first connect the ground connection to the GND connector, and then connect the positive supply to the
VDD connector. Verify that the connections are made to the correct banana jacks.
2.1.2 Inputs and Outputs
2.1.2.1 Audio
1. Verify that the audio source is set to the minimum level.
2. Connect the audio source to the inputs, LIN and RIN. Shunt JP1 and JP2 for single-ended input.
3. Connect a headset or other load to the headphone jack.
2.1.2.2 Shutdown Controls
1. Shutdown is controlled by pushbutton S1. Press and hold S1 to place the TPA6138A2 in shutdown.
Release S1 to reactivate the TPA6138A2.
2.1.3 Power Up
1. Verify the correct connections as described in the Power and Ground and Inputs and Outputs sections.
2. Verify the correct voltage setting of the power supply and turn ON the power supply. Proper operation
of the EVM should begin.
3. Adjust the audio signal source as needed.
3
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15.0K
0603
R6
GND
1.0ufd/16V 0603
C18
GND
10K
0603
R12
2.20K 0603
R13
22.0K
0603
R14
GND
GND
0.5in 0.5in 0.5in 0.5in
180pfd/50V 0805
C7
1
2
J1
GND
GND
S1
GND
R3
0603
100K 100K
0603
R2
GND
100K
0603
R5 R4
0603
100K
R7
0603
15.0K 15.0K
0603
R9
43.0K
0603
R16 R17
0603
43.0K
R15
0603
30.0K
C17
0603 1.0ufd/16V
GND
+3.3V
GND
GND
10
0603
R22
C19
0603 1000pfd/50V
GND
R23
0603
10
1000pfd/50V 0603
C20
GND
GND
43.0K
0603
R18
R11
0603
15.0K
180pfd/50V 0805
C8
C2
0603 0.1ufd/10V
+3.3V
+3.3V
3.3V
0805
Green
R1
0603
392
UVP
Red
GND
0.1ufd/10V 0603
C14
1234567
89
1011121314
U1
TSSOP14-PW
TPA6138A2PW
R21
0603
10K
+3.3V
C13
0603
100pfd/50V GND
MUTE
Orange
30.0K
0603
R20
43.0K
0603
R19
47pfd/50V 0603
C12
1
2
JP3
GND
47pfd/50V 0603
C9
30.0K 0603
R8
GND GND
C10
0603 47pfd/50V
R10
0603 30.0K
GND GND
47pfd/50V 0603
C11
1
2
JP1
GND
JP2 2
1
RIN
RCA (Red)
1
2
3
LIN 3
2
1
RCA (Black)
10ufd/6.3V 0805 C1 1.0ufd/16V
0603
C15
Orange
HPL
HPOUT
3.5mm (Lime Green)
Left
Right
Shield
3
5
2 4
1
HPR
Orange
Black
GND
GND
GND
2.2ufd/50V
C3
VSA
+
VSA
C4
2.2ufd/50V
+
2.2ufd/50V
C5
VSA
+
VSA
C6
2.2ufd/50V
+
HEADPHONE
OUTPUT
DUAL FOOTPRINT PADS
C0603 CERAMIC/SMD-VSA ELECTROLYTIC
MUTE HEAD PHONE
STANDOFFS
HEADPHONE
IN
POWER SUPPLY IN DO NOT POPULATE
Reference www.ti.com
3 Reference
This section includes the EVM schematic, board layout reference, and parts list.
3.1 TPA6138A2EVM Schematic
4TPA6138A2 EVM SLOU305A–November 2010–Revised January 2011
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3.2 TPA6138A2EVM PCB Layers
Figure 3. Top Layer
Figure 4. Bottom Layer
5
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TPA6138A2EVM Bill of Materials www.ti.com
4 TPA6138A2EVM Bill of Materials
Table 1. TPA6138A2EVM Bill of Materials
Qty. Manfacturer Part No. Ref Des Description Manufacturer
1 TPA6138A2PW U1 DIRECTPATH 2V AUDIO LINE DRIVER W/ADJ GAIN TEXAS INSTRUMENTS
TSSOP14-PW ROHS
1 SML-LXT0805GW-TR 3.3V LED, GREEN 2.0V SMD0805 ROHS LUMEX OPTO
4 GRM1885C1H470JA01D C9, C10, C11, C12 CAP SMD0603 CERM 47PFD 50V 5% COG ROHS MURATA
1 GRM1885C1H101JA01D C13 CAP SMD0603 CERM 100PFD 50V 5% COG ROHS MURATA
2 CC0805JRNP09BN181 C7, C8 CAP SMD0805 CERM 180PFD 50V 5% NPO ROHS YAGEO
2 C1608C0G1H102J C19, C20 CAP SMD0603 CERM 1000PFD 50V 5% COG ROHS TDK CORP.
1 C0603C104K8RACTU C2 CAP SMD0603 CERM 0.1UFD 10V 5% X7R ROHS KEMET
4 C1608X7R1C105K C15, C17, C18 CAP SMD0603 CERM 1.0UFD 16V 10% X7R ROHS TDK
4 EEE-1HS2R2SR C3, C4, C5, C6 CAP ALUM-ELECT SMD-VSA 2.2UFD 50V 20% ROHS PANASONIC
1 08056C106KAT2A C1 CAP SMD0805 CERM 10UFD 6.3V X7R 10% ROHS AVX
2 RC0603JR-0710RL R22, R23 RESISTOR SMD0603 THICK FILM 10 OHMS 5% 1/10W ROHS YAGEO
1 ERJ-3EKF3920V R1 RESISTOR SMD0603 392 OHM 1% THICK FILM 1/10W ROHS PANASONIC
1 ERJ-3GEYJ103V R21 RESISTOR SMD0603 10K 5% 1/10W ROHS PANASONIC
4 RMCF0603FT15K0 R6, R7, R9, R11 RESISTOR SMD0603 15.0K OHMS 1% 1/10W ROHS STACKPOLE ELECTRONICS
4 RC0603FR-0743KL R16, R17, R18, R19 RESISTOR SDM0603 20.0K OHM 1% THICK FILM 1/16W YAGEO
ROHS
4 RC0603FR-0730KL R8, R10, R15, R20 RESISTOR SMD0603 THICK FILM 30.0K 1% 1/10W ROHS YAGEO
4 RMCF0603JT100K R2, R3, R4, R5 RESISTOR SMD0603 100K OHMS 5% 1/10W ROHS STACKPOLE ELECTRONICS
4 PBC02SAAN J1, JP1, JP2, JP3 HEADER THRU MALE 2 PIN 100LS GOLD ROHS SULLINS
1 PJRAN1X1U01X LIN JACK, RCA 3-PIN PCB-RA BLACK ROHS SWITCHCRAFT
1 PJRAN1X1U03X RIN JACK, RCA 3-PIN PCB-RA RED ROHS SWITCHCRAFT
1 STX-3150-5N-577C HPOUT JACK MINI STEREO 3.5mm LIME GREEN W/SHUNTS ROHS KYCON
1 5000 UVP PC TESTPOINT, RED, ROHS KEYSTONE ELECTRONICS
1 5001 GND PC TESTPOINT BLACK ROHS KEYSTONE ELECTRONICS
3 5003 HPL, HPR, MUTE PC TESTPOINT ORANGE ROHS KEYSTONE ELECTRONICS
1 TL1015AF160QG S1 SWITCH, MOM, 160G SMT 4X3MM ROHS E-SWITCH
3 SPC02SYAN JP1, JP2, JP3 SHUNT, BLACK AU FLASH 0.100LS SULLINS
4 PMS 440 0025 PH NA 4-40 SCREW, STEEL 0.250 IN BUILDING FASTENERS
4 2027 NA STANDOF ,4-40 0.5IN 3/16IN DIA ALUM RND F-F KEYSTONE ELECTRONICS
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FCC Warning
This evaluation board/kit is intended for use for ENGINEERING DEVELOPMENT, DEMONSTRATION, OR EVALUATION
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EVM Warnings and Restrictions
It is important to operate this EVM within the input voltage range of 0 V to 3 V and the output voltage range of 0 V to 3.3 V .
Exceeding the specified input range may cause unexpected operation and/or irreversible damage to the EVM. If there are
questions concerning the input range, please contact a TI field representative prior to connecting the input power.
Applying loads outside of the specified output range may result in unintended operation and/or possible permanent damage to the
EVM. Please consult the EVM User's Guide prior to connecting any load to the EVM output. If there is uncertainty as to the load
specification, please contact a TI field representative.
During normal operation, some circuit components may have case temperatures greater than 85°C. The EVM is designed to
operate properly with certain components above 85°C as long as the input and output ranges are maintained. These components
include but are not limited to linear regulators, switching transistors, pass transistors, and current sense resistors. These types of
devices can be identified using the EVM schematic located in the EVM User's Guide. When placing measurement probes near
these devices during operation, please be aware that these devices may be very warm to the touch.
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