Product
Folder
Sample &
Buy
Support &
Community
Tools &
Software
Technical
Documents
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
LM48560 Boomer™ Audio Power Amplifier Series High Voltage Class H Ceramic Speaker
Driver With Automatic Level Control
1 Features
3 Description
•
•
•
•
•
The LM48560 device is a high voltage, high
efficiency, Class H driver for ceramic speakers and
piezo actuators. The LM48560 device’s Class H
architecture offers significant power savings
compared to traditional Class AB amplifiers. The
device provides 30 VP-P output drive while consuming
just 4 mA of quiescent current from a 3.6 V supply.
1
•
•
•
•
•
•
Class H Topology
Integrated Boost Converter
Bridge-Tied Load (BTL) Output
Selectable Differential Inputs
Selectable Control Interfaces
– (Hardware or Software mode)
I2C Programmable ALC
Low Supply Current
Minimum External Components
Micro-Power Shutdown
Available in Space-Saving DSBGA Package
Key Specifications:
– Output Voltage at VDD = 3.6 V,
RL = 1.5 μF + 10 Ω, THD+N ≤ 1%
– 30 VP-P (Typical)
– Quiescent Power Supply Current
at 3.6 V (ALC Enabled)
– 4 mA (Typical)
– Power Dissipation at 25 VP-P, 1 W (Typical)
– Shutdown Current, 0.1 μA (Typical)
The LM48560 device features TI’s unique automatic
level control (ALC) that provides output limiter
functionality. The LM48560 device features two fully
differential inputs with separate gain settings, and a
selectable control interface. In software control mode,
the gain control and device modes are configured
through the I2C interface. In hardware control mode,
the gain and input mux are configured through a pair
of logic inputs.
The LM48560 device has a low power shutdown
mode that reduces quiescent current consumption to
0.1 μA. The LM48560 device is available in an ultrasmall 16–bump DSBGA package (1.97 mm × 1.97
mm).
Device Information(1)
PART NUMBER
PACKAGE
LM48560
2 Applications
•
•
•
•
Touch Screen Smart Phones
Tablet PCs
Portable Electronic Devices
MP3 Players
DSBGA (16)
BODY SIZE (NOM)
1.97 mm × 1.97 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application Circuit
+2.7V to +5.5V
D1
L1
4.7 PH
CS
VDD
SW
VBST
SCL/GAIN
SDA/SEL
SW/HW
CBST
BOOST
CONVERTER
I2C
INTERFACE
PGND
SHDN
CIN
0.47 PF
1 PF
IN1+
CIN
OUT-
0.47 PF
CIN
0.47 PF
IN1IN2+
MUX/
GAIN
STAGE
ALC
RL
10:
OUT+
CIN
0.47 PF
SET
CL
IN2SGND
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
Table of Contents
1
2
3
4
5
6
7
8
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
4
4
4
5
6
7
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Electrical Characteristics VDD = 3.6 V .......................
I2C Interface Characteristics .....................................
Typical Characteristics ..............................................
8.4 Device Functional Modes........................................ 13
8.5 Programming .......................................................... 14
8.6 Register Maps ......................................................... 15
9
Application and Implementation ........................ 17
9.1 Application Information............................................ 17
9.2 Typical Application ................................................. 17
10 Power Supply Recommendations ..................... 20
11 Layout................................................................... 20
11.1 Layout Guidelines ................................................. 20
11.2 Layout Example .................................................... 20
12 Device and Documentation Support ................. 21
12.1
12.2
12.3
12.4
Parameter Measurement Information ................ 10
Detailed Description ............................................ 11
8.1 Overview ................................................................. 11
8.2 Functional Block Diagram ....................................... 11
8.3 Feature Description................................................. 11
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
21
21
21
21
13 Mechanical, Packaging, and Orderable
Information ........................................................... 21
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
2
Rev
Date
1.0
08/16/11
Initial WEB released.
Description
1.01
09/21/11
Input edits under CLASS H OPERATION.
1.02
11/01/11
Edited curves 30150753, 54, 55, 56, and Figure 26 (I2C Read Cycle).
1.03
11/10/11
Edited Figure 26.
1.04
07/25/12
Input texts/limits edits in the EC table.
1.05
08/22/12
Edited Table 1 and Table 2.
E
05/02/2013
Changed layout of National Data Sheet to TI format.
F
10/21/2015
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application
and Implementation section, Power Supply Recommendations section, Layout section, Device
and Documentation Support section, and Mechanical, Packaging, and Orderable Information
section.
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
5 Pin Configuration and Functions
YZR Package
16-Pin DSBGA
Top View
4
IN1+
IN2+
SDA/SEL
PGND
3
IN1-
IN2-
SCL/
GAIN
SW
2
SGND
SHDN
SW/HW
VDD
1
OUT+
OUT-
VBST
SET
C
D
A
B
Pin Functions
PIN
NO.
NAME
I/O
DESCRIPTION
A1
OUT+
O
Amplifier Non-Inverting Output
A2
SGND
—
Amplifier Ground
A3
IN1–
I
Amplifier Inverting Input 1
A4
IN1+
I
Amplifier Non-Inverting Input 1
B1
OUT–
O
Amplifier Inverting Output
B2
SHDN
I
Active Low Shutdown. Connect SHDN to GND to disable device.
Connect SHDN to VDD for normal operation
B3
IN2–
I
Amplifier Inverting Input 2
B4
IN2+
I
Amplifier Non-Inverting Input 2
C1
VBST
—
C2
SW/HW
I
Mode Selection Control:
SW/HW = 0 → Hardware Mode
SW/HW = 1 → Software Mode
C3
SCL/GAIN
I
I2C Serial Clock Input (Software Mode)
Gain Select Input (Hardware Mode)
see (Table 5)
C4
SDA/SEL
I/O
I2C Serial Data Input (Software Mode)
Amplifier Input Select (Hardware Mode)
see (Table 5)
D1
SET
—
ALC Timing Input
D2
VDD
—
Power Supply
D3
SW
—
Boost Converter Switching Node
D4
PGND
—
Boost Converter Ground
Boost Converter Output
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
3
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
MAX
UNIT
VDD
Supply voltage (2)
MIN
6
V
SW
Voltage
25
V
VBST
Voltage
21
V
VDD 0.3
V
Input voltage
Power dissipation
–0.3
(3)
TJ
Junction temperature
Tstg
Storage temperature
(1)
(2)
(3)
Internally limited
–65
150
°C
150
°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
All voltages are measured with respect to the ground pin, unless otherwise specified.
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJMAX, θJA, and the ambient temperature,
TA. The maximum allowable power dissipation is PDMAX = (TJMAX –TA) / θJA or the given in Absolute Maximum Ratings, whichever is
lower.
6.2 ESD Ratings
VALUE
V(ESD)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)
±2000
Charged-device model (CDM), per JEDEC specification JESD22C101 (2)
±500
Machine Model
(1)
(2)
(3)
(3)
UNIT
V
±100
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
Machine model, applicable std. JESD22-A115-A.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
UNIT
TA
Operating free-air temperature
–40
85
°C
VDD
Supply voltage
2.7
5.5
V
4
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
6.4 Electrical Characteristics VDD = 3.6 V
The following specifications apply for RL = 1.5 μF + 10 Ω, CBST = 1 μF, CIN = 0.47 μF, CSET = 100 nF, AV = 24 dB unless
otherwise specified. Limits apply for TA = 25 °C. (1) (2)
PARAMETER
VDD
Supply voltage
IDD
Quiescent power supply current
TEST CONDITIONS
MIN
(3)
TYP
(4)
2.7
MAX
(3)
UNIT
5.5
V
VIN = 0 V, RL = ∞
PD
Power consumption
ISD
Shutdown current
TWU
Wake-up time
VOS
Differential output offset voltage
ALC Enabled
4
ALC Disabled
3.6
mA
1
W
VOUT = 25 VP-P, f = 1 kHz
2.5
4.4
Hardware Mode
0.1
2
From Shutdown
15
AV = 24 V
10
90
mV
5
20
mV
0
0.5
AV = 0 dB (Boost Disabled)
GAIN = 0
IN1
IN2
Boost Disabled
Gain (software mode)
Boost Enabled
0.5
Input resistance
µA
µA
ms
GAIN = 1
5.5
6
6.5
GAIN = 0
23.5
24
24.5
GAIN = 1
29.5
30
30.5
GAIN1 = 0, GAIN0 = 0
–0.5
0
0.5
GAIN1 = 0, GAIN0 = 1
5.5
6
6.5
GAIN1 = 1, GAIN0 = 0
11.5
12
12.5
GAIN1 = 1, GAIN0 = 1
17.5
18
18.5
GAIN1 = 0, GAIN0 = 0
20.5
21
21.5
GAIN1 = 0, GAIN0 = 1
23.5
24
24.5
GAIN1 = 1, GAIN0 = 0
26.5
27
27.5
GAIN1 = 1, GAIN0 = 1
29.5
30
30.5
Gain step size (software mode)
RIN
mA
Software Mode
Gain (Hardware Mode)
AV
6
dB
dB
dB
3
AV
dB
0 dB
46
50
58
30 dB
46
50
58
200 Hz
25
30
1 kHz
25
30
kΩ
THD+N = 1%
VOUT
Output voltage
f
THD+N Total harmonic distortion + noise VOUT = 18 VP-P, f = 1 kHz
VP-P
0.08%
VDD = 3.6 V + 200 mVP-P sine, Inputs = AC GND
PSRR
Power supply rejection ratio
(Figure 22)
fRIPPLE = 217 Hz
55
fRIPPLE = 1 kHz
78
dB
76
VCM = 200 mVP-P sine
CMRR
SNR
Common mode rejection ratio
(Figure 23)
Signal-to-noise-ratio
fRIPPLE = 217 Hz
68
dB
fRIPPLE = 1k Hz
78
dB
Boost Disabled, A-weighted
107
dB
Boost Enabled A-weighted
98
dB
A-weighted
εOS
(1)
(2)
(3)
(4)
Output noise
AV
24 dB
0 dB (Boost Disabled)
134
16
μVRMS
All voltages are measured with respect to the ground pin, unless otherwise specified.
The Electrical Characteristics tables list ensured specifications under the listed Recommended Operating Conditions except as
otherwise modified or specified by the Electrical Characteristics Conditions and/or Notes. Typical specifications are estimations only and
are not ensured.
Datasheet min/max specification limits are ensured by design, test, or statistical analysis.
Typical values represent most likely parametric norms at TA = 25 ºC, and at the Recommended Operation Conditions at the time of
product characterization and are not ensured.
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
5
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
Electrical Characteristics VDD = 3.6 V (continued)
The following specifications apply for RL = 1.5 μF + 10 Ω, CBST = 1 μF, CIN = 0.47 μF, CSET = 100 nF, AV = 24 dB unless
otherwise specified. Limits apply for TA = 25 °C.(1)(2)
PARAMETER
TEST CONDITIONS
MIN
(3)
TYP
(4)
MAX
(3)
UNIT
TA
Attack time
ATK1:ATK0 = 00, CSET = 100 nF
0.83
ms
TR
Release time
RLT1:RLT0 = 00, CSET = 100 nF
0.5
s
fSW
Boost converter switching
frequency
ILIMIT
Boost converter current limit
VIH
Logic high input threshold
SHDN
VIL
Logic low input threshold
SHDN
IIN
Input leakage current
SHDN
2
MHz
1.5
A
1.4
V
0.1
0.5
V
0.2
μA
6.5 I2C Interface Characteristics
The following specifications apply for RPU = 1 kΩ to VDD, SW/HW = 1 (Software Mode) unless otherwise specified. Limits
apply for TA = 25 °C. (1) (2)
PARAMETER
TEST CONDITIONS
VIH
Logic Input High Threshold
SDA, SCL
VIL
Logic Input Low Threshold
SDA, SCL
MIN
(3)
TYP
(4)
MAX
(3)
1.1
SCL Frequency
UNIT
V
0.5
V
400
kHz
t1
SCL Period
2.5
μs
t2
SDA Setup Time
250
ns
t3
SDA Stable Time
250
ns
t4
Start Condition Time
250
ns
t5
Stop Condition Time
250
ns
(1)
(2)
(3)
(4)
All voltages are measured with respect to the ground pin, unless otherwise specified.
The Electrical Characteristics tables list ensured specifications under the listed Recommended Operating Conditions except as
otherwise modified or specified by the Electrical Characteristics Conditions and/or Notes. Typical specifications are estimations only and
are not ensured.
Typical values represent most likely parametric norms at TA = 25 ºC, and at the Recommended Operation Conditions at the time of
product characterization and are not ensured.
Charge device model, applicable std. JESD22-C101-C.
Figure 1. I2C Timing Diagram
SDA
SCL
S
P
START condition
STOP condition
Figure 2. Start and Stop Diagram
6
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
6.6 Typical Characteristics
All typical performance curves are taken with conditions seen in Typical Characteristics, unless otherwise specified.
50
50
20
10
5
2
THD + N (%)
VOUT = 25 VP-P
5
THD + N (%)
VOUT = 30 VP-P
20
VOUT = 30 VP-P
10
VOUT = 18 VP-P
1
0.5
0.2
VOUT = 25 VP-P
2
VOUT = 18 VP-P
1
0.5
0.2
0.1
0.1
0.05
0.05
0.02
0.02
0.01
0.01
20
50
100 200
500
1k
2k
5k
10k
20k
20
50
500
1k
2k
5k
10k
20k
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 3. THD+N vs Frequency
CL = 0.6 μF, VDD = 3.6 V, Boosted, AV = 24 dB
Figure 4. THD+N vs Frequency
CL = 1 μF, VDD = 3.6 V, Boosted, AV = 24 dB
50
20
10
5
VOUT = 30 VP-P
2
1
10
VOUT = 25 VP-P
5
0.5
2
THD+N (%)
THD + N (%)
100 200
VOUT = 18 VP-P
1
0.5
0.2
0.2
0.1
0.05
0.02
0.01
0.005
0.1
0.05
0.02
0.002
0.001
20
0.01
20
50
100 200
500
1k
2k
5k
10k
20k
5k 10k 20k
Figure 6. THD+N vs Frequency
VDD = 3.6 V, CL = 0.6 μF, VOUT = 5 VP-P
Unboosted, AV = 0 dB
Figure 5. THD+N vs Frequency
CL = 1.5 μF, VDD = 3.6 V, Boosted, AV = 24 dB
10
5
10
5
2
1
2
1
0.5
THD+N (%)
0.5
THD+N (%)
50 100 200 500 1k 2k
FREQUENCY (Hz)
FREQUENCY (Hz)
0.2
0.1
0.05
0.2
0.1
0.05
0.02
0.01
0.005
0.02
0.01
0.005
0.002
0.001
20
0.002
0.001
20
50 100 200 500 1k 2k
5k 10k 20k
50 100 200 500 1k 2k
5k 10k 20k
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 7. THD+N vs Frequency
VDD = 3.6 V, CL = 1 μF, VOUT = 5 VP-P
Unboosted , AV = 0 dB
Figure 8. THD+N vs Frequency
VDD = 3.6 V, CL = 1.5 μF, VOUT = 5 VP-P
Unboosted, AV = 0 dB
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
7
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
Typical Characteristics (continued)
35
8
30
7
OUTPUT VOLTAGE (Vp-p)
OUTPUT VOLTAGE (Vp-p)
All typical performance curves are taken with conditions seen in Typical Characteristics, unless otherwise specified.
25
20
15
10
5
6
5
4
3
2
1
0
10
100
1000
10000
100000
0
10
100
1000
FREQUENCY (Hz)
f = 4 kHz
f = 3 kHz
1
0.1
f = 2 kHz
0.01
f = 1 kHz
f = 200 Hz
0.001
0.01
0.1
1
10
100
Figure 10. Output Voltage vs Frequency
CL = 1.5 μF, THD+N ≤ 1%, Unboosted
TOTAL HARMONIC DISTORTION + NOISE (%)
TOTAL HARMONIC DISTORTION + NOISE (%)
100
10
100
f = 4 kHz
f = 5 kHz
f = 3 kHz
10
1
0.1
f = 2 kHz
f = 1 kHz
0.01
f = 200 Hz
0.001
0.01
0.1
1
10
100
OUTPUT VOLTAGE (Vp-p)
Figure 11. THD+N vs Output Voltage
CL = 0.6 μF, VDD = 3.6 V, Boosted, AV = 24 dB
Figure 12. THD+N vs Output Voltage
CL = 1 μF, VDD = 3.6 V, Boosted, AV = 24 dB
100
f = 4 kHz
f = 5 kHz
f = 3 kHz
10
1
0.1
f = 2 kHz
f = 1 kHz
0.01
f = 200 Hz
0.001
0.01
100
50
20
10
5
2
1
0.5
0.2
0.1
0.05
0.02
0.01
0.005
0.002
0.001
0.0005
0.0002
0.0001
1m
f = 1 kHz
f = 2 kHz
THD+N (%)
TOTAL HARMONIC DISTORTION + NOISE (%)
OUTPUT VOLTAGE (Vp-p)
0.1
1
10
100
Figure 13. THD+N vs Output Voltage
CL = 1.5 μF, VDD = 3.6 V, Boosted, AV = 24 dB
f = 200 Hz
5m
2m
OUTPUT VOLTAGE (Vp-p)
8
100000
FREQUENCY (Hz)
Figure 9. Output Voltage vs Frequency
CL = 1.5 μF, THD+N ≤ 1%, Boosted
f = 5 kHz
10000
10m
20m 100m 500m
1
50m 200m
2
4
OUTPUT VOLTAGE (Vp-p)
Figure 14. THD+N vs Output Voltage
CL = 1.5 μF, VDD = 3.6 V, Unboosted, AV = 0 dB
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
Typical Characteristics (continued)
12
11.5
11
10.5
10
9.5
9
8.5
8
7.5
7
6.5
6
5.5
5
4.5
4
3.5
3
2.5
2
1.5
1
500m
ALC Off
VOUT = 22VP-P
VOUT = 20VP-P
Supply Current (mA)
OUTPUT VOLTAGE (V)
All typical performance curves are taken with conditions seen in Typical Characteristics, unless otherwise specified.
VOUT = 14VP-P
VOUT = 25VP-P
VOUT = 17VP-P
VOUT = 28VP-P
0
200m
400m
600m
800m
100m
300m
500m
700m
0.9
1
1.1
3
2.8
2.6
2.4
2.2
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4
INPUT VOLTAGE (V)
Supply Voltage (V)
Figure 15. Input Voltage vs Output Voltage
ALC Enabled, AV = 21 dB, VDD = 3.6 V
Figure 16. Supply Current vs Supply Voltage
RL = ∞
2500
TOTAL POWER CONSUMPTION (mW)
TOTAL POWER CONSUMPTION (mW)
1000
900
4 kHz
800
700
600
2 kHz
500
400
1 kHz
300
200
200 Hz
100
0
1500
2 kHz
1000
1 kHz
500
200 Hz
0
0
5
10
15
25
20
30
35
4 kHz
2000
0
5
15
20
25
30
35
Figure 18. Total Power Consumption vs Output Voltage
VDD = 3.6 V, CL = 1 μF
Figure 17. Total Power Consumption vs Output Voltage
VDD = 3.6 V, CL = 0.6 μF
4500
0
4000
-10
4 kHz
3500
-20
3000
-30
2 kHz
CMRR (dB)
TOTAL POWER CONSUMPTION (mW)
10
VOUT (VPP)
VOUT (VPP)
2500
2000
1 kHz
1500
-40
-50
-60
1000
-70
200 Hz
500
-80
0
0
5
10
15
20
25
30
35
-90
10
VOUT (VPP)
100
1000
10000
100000
FREQUENCY (Hz)
Figure 19. Total Power Consumption vs Output Voltage
VDD = 3.6 V, CL = 1.5 μF
Figure 20. Common Mode Rejection Ratio vs Frequency
VCM= 200 mVP-P, CIN = 10 μF, VDD = 3.6 V, CL = 1.5 μF
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
9
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
Typical Characteristics (continued)
All typical performance curves are taken with conditions seen in Typical Characteristics, unless otherwise specified.
+0
-10
-20
PSRR (dB)
-30
-40
-50
-60
-70
-80
-90
-100
20
50
100 200
500
1k
2k
5k
10k
20k
FREQUENCY (Hz)
Figure 21. Power Supply Rejection Ratio vs Frequency
VRIPPLE = 200 mVP-P, VDD = 3.6 V, CL = 1.5 μF
7 Parameter Measurement Information
200 mVp-p
ANALYZER
VDD
+
VDD
-
IN+
ZL
DUT
IN-
Figure 22. PSRR Test Circuit
VDD
ANALYZER
+
VDD
IN+
IN-
DUT
ZL
200 mVp-p
Figure 23. CMRR Test Circuit
10
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
8 Detailed Description
8.1 Overview
The LM48560 device is a fully differential Class H driver for ceramic speakers and piezo actuators. The
integrated, high efficiency boost converter dynamically adjusts the amplifier’s supply voltage based on the output
signal to maintain sufficient headroom while improving efficiency. The LM48560 device’s Class H architecture
offers significant power savings compared to conventional Class AB drivers. The LM48560 features two fully
differential inputs with separate gain settings, and a selectable control interface. In software control mode, the
gain control and device modes are configured through the I2C interface. In hardware control mode, the gain and
input mux are configured through a pair of logic inputs.
8.2 Functional Block Diagram
+2.7V to +5.5V
D1
L1
4.7 PH
CS
VDD
SW
VBST
SCL/GAIN
SDA/SEL
SW/HW
CBST
BOOST
CONVERTER
I2C
INTERFACE
PGND
SHDN
CIN
0.47 PF
1 PF
IN1+
CIN
OUT-
0.47 PF
CIN
0.47 PF
IN1IN2+
MUX/
GAIN
STAGE
ALC
RL
10:
OUT+
CIN
0.47 PF
SET
CL
IN2SGND
8.3 Feature Description
8.3.1 General Amplifier Function
The LM48560 device is a fully differential, Class H piezo driver for ceramic speakers and haptic actuators. The
integrated, high efficiency boost converter dynamically adjusts the amplifier’s supply voltage based on the output
signal, increasing headroom and improving efficiency compared to a conventional Class AB driver. The fully
differential amplifier takes advantage of the increased headroom and bridge-tied load (BTL) architecture,
delivering significantly more voltage than a single-ended amplifier.
8.3.2 Class H Operation
Class H is a modification of another amplifier class (typically Class B or Class AB) to increase efficiency and
reduce power dissipation. To decrease power dissipation, Class H uses a tracking power supply that monitors
the output signal and adjusts the supply accordingly. When the amplifier output is below 3VP-P, the nominal boost
voltage is 6 V. As the amplifier output increases above 3 VP-P, the boost voltage tracks the amplifier output as
shown in Figure 24. When the amplifier output falls below 3 VP-P, the boost converter returns to its nominal output
voltage. Power dissipation is greatly reduced compared to conventional Class AB drivers.
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
11
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
Feature Description (continued)
VBOOST
(2V/DIV)
VOUT
(2V/DIV)
2 ms/DIV
Figure 24. Class H Operation
8.3.3 Differential Amplifier Explanation
The LM48560 device features a fully differential amplifier. A differential amplifier amplifies the difference between
the two input signals. A major benefit of the fully differential amplifier is the improved common mode rejection
ratio (CMRR) over single ended input amplifiers. The increased CMRR of the differential amplifier reduces
sensitivity to ground offset related noise injection, especially important in noisy systems.
8.3.4 Automatic Level Control (ALC)
The ALC is available in software mode only, and only in boosted mode. In hardware mode ALC is always
disabled. The ALC limits the peak output voltage to the programmed value. Consequently, it limits the peak boost
voltage, as this is derived from the output voltage. The ALC is continuous, in that it provides a continuous
adjustment of the voltage gain to limit the output voltage to the programmed value. The available gain adjustment
range is typically 8 dB. When the input amplitude is further increased beyond the ALC attenuation range, the
output will again increase. This is illustrated in the Typical Performance Graphs, as seen on the 14 VPP plot in the
Input voltage vs Output Voltage curve. The attack and decay of the ALC is programmed by software and works
in conjunction with the external capacitor CSET. Typically CSET is 0.1 μF, although it can be changed from 0.1 μF
to 4.7 μF to select other ranges of attack and decay time.
8.3.5 Attack Time
Attack time (tATK) is the time it takes for the gain to be reduced by 6 dB once the audio signal exceeds the ALC
threshold. Fast attack times allow the ALC to react quickly and prevent transients such as symbol crashes from
being distorted. However, fast attack times can lead to volume pumping, where the gain reduction and release
becomes noticeable, as the ALC cycles quickly. Slower attack times cause the ALC to ignore the fast transients,
and instead act upon longer, louder passages. Selecting an attack time that is too slow can lead to increased
distortion in the case of the No Clip function, and possible output overload conditions in the case of the Voltage
limiter. The attack time is set by a combination of the value of CSET and the attack time coefficient as given by
Equation 1:
tATK = 20 kΩCSET / αATK
(1)
Where αATK is the attack time coefficient (Table 1) set by bits B4:B3 in the Voltage Limit Control Register. The
attack time coefficient allows the user to set a nominal attack time. The internal 20 kΩ resistor is subject to
temperature change, and it has tolerance between –11% to +20%.
Table 1. Attack Time Coefficient
12
B4
B3
αATK
0
0
2.4
0
1
1.7
1
0
1.3
1
1
0.9
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
8.3.6 Release Time
Release time (tRL) is the time it takes for the gain to return from 6 dB to its normal level once the audio signal
returns below the ALC threshold. A fast release time allows the ALC to react quickly to transients, preserving the
original dynamics of the audio source. However, similar to a fast attack time, a fast release time contributes to
volume pumping. A slow release time reduces the effect of volume pumping. The release time is set by a
combination of the value of CSET and release time coefficient as given by Equation 2:
tRL = 20 MΩCSET / αRL
(s)
(2)
where αRL is the release time coefficient (Table 2) set by bits B6:B5 in the No Clip Control Register. The release
time coefficient allows the user to set a nominal release time. The internal 20 MΩ is subject to temperature
change, and it has tolerance between -11% to +20%.
Table 2. Release Time Coefficient
αRL
B6
B5
0
0
4
0
1
5.3
1
0
9.5
1
1
11.8
8.3.7 Boost Converter
The LM48560 device features an integrated boost converter with a dynamic output control. The device monitors
the output signal of the amplifier, and adjusts the output voltage of the boost converter to maintain sufficient
headroom while improving efficiency.
8.3.8 Gain Setting
The LM48560 device features four internally configured gain settings 0 db, 6 dB, and 30 dB. The device gain is
selected through a single pin (GAIN). The gain settings are shown in Table 3.
Table 3. Gain Setting
GAIN
GAIN SETTING
IN1
GAIN SETTING
IN2
0
0 dB
24 dB
1
6 dB
30 dB
8.3.9 Shutdown Function
The LM48560 device features a low current shutdown mode. Set SD = GND to disable the amplifier and boost
converter and reduce supply current to 0.01 µA.
8.4 Device Functional Modes
8.4.1 Software or Hardware Mode
Device operation in hardware or software mode is determined by the state of the SW/HW pin. Connect SW/HW
to ground for hardware mode, and connect to VDD for software mode.
SW/HW
0
SDA/SEL
0
(Boost Disabled)
1
(Boost Enabled)
1
SDA
SCL/GAIN
MODE
0
IN1, Av = 0
1
IN1, Av = 6
0
IN2, Av = 24
1
IN2, Av = 30
SCL
I2C Mode
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
13
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
8.4.2 Single-Ended Input Configuration
The LM48560 device is compatible with single-ended sources. When configured for single-ended inputs, input
capacitors must be used to block and DC component at the input of the device. Figure 25 shows the typical
single-ended applications circuit.
LM48560
SINGLE-ENDED
INPUT
IN-
IN+
Figure 25. Single-Ended Input Configuration
8.5 Programming
8.5.1 Read/Write I2C Compatible Interface
The LM48560 device is controlled through an I2C compatible serial interface that consists of a serial data line
(SDA) and a serial clock (SCL). The clock line is uni-directional. The data line is bi-directional (open drain). The
LM48560 device and the master can communicate at clock rates up to 400 kHz. Figure 1 shows the I2C interface
timing diagram. Data on the SDA line must be stable during the HIGH period of SCL. The LM48560 device is a
transmit/receive slave-only device, reliant upon the master to generate the SCL signal. Each transmission
sequence is framed by a START condition and a STOP condition Figure 2. Each data word, device address and
data, transmitted over the bus is 8 bits long and is always followed by an acknowledge pulse Figure 26. The
LM48560 device address is 1101111.
8.5.2 Write Sequence
The example write sequence is shown in Figure 26. The START signal, the transition of SDA from HIGH to LOW
while SDA is HIGH, is generated, altering all devices on the bus that a device address is being written to the bus.
The 7-bit device address is written to the bus, most significant bit (MSB) first, followed by the R/W bit (R/W = 0
indicating the master is writing to the LM48560 device). The data is latched in on the rising edge of the clock.
Each address bit must be stable while SDA is HIGH. After the R/W bit is transmitted, the master device releases
SDA, during which time, an acknowledge clock pulse is generated by the slave device. If the LM48560 device
receives the correct address, the device pulls the SDA line low, generating and acknowledge bit (ACK).
Once the master device registers the ACK bit, the 8-bit register address word is sent, MSB first. Each data bit
should be stable while SCL is HIGH. After the 8-bit register address is sent, the LM48560 device sends another
ACK bit. Upon receipt of the acknowledge, the 8-bit register data is sent, MSB first. The register data word is
followed by an ACK, upon receipt of which, the master issues a STOP bit, allowing SDA to go high while SDA is
high.
SCL
SDA
START
MSB
DEVICE ADDRESS
LSB
R/W ACK
REGISTER ADDRESS
ACK
REGISTER DATA
ACK
STOP
Figure 26. Example I2C Write Cycle
8.5.3 Read Sequence
The example read sequence is shown in Figure 27. The START signal, the transition of SDA from HIGH to LOW
while SDA is HIGH, is generated, altering all devices on the bus that a device address is being written to the bus.
14
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
Programming (continued)
The 7-bit device address is written to the bus, followed by the R/W = 1 (R/W = 1 indicating the master wants to
read data from the LM48560 device). After the R/W bit is transmitted, the master device releases SDA, during
which time, an acknowledge clock pulse is generated by the slave device. If the LM48560 device receives the
correct address, the device pulls the SDA line low, generating and acknowledge bit (ACK). Once the master
device registers the ACK bit, the 8-bit register address word is sent, MSB first, followed by an ACK and selected
register data from the LM48560 device. The register data is sent MSB first. Following the acknowledgment of the
register data word [7:0], the master issues a STOP bit, allowing SDA to go high while SDA is high.
ack from slave repeated start
ack from slave
start
MSB Device Address
LSB
w ack MSB Register 0x00h LSB ack rs
ack from slave data from slave ack from master
MSB Device Address
LSB
r ack MSB
Data
LSB ack stop
SCL
SDA
start
Device address =
1101111
w ack register address = 0x00h ack
rs
Device address =
1101111
r ack
register 0x00h data
ack stop
Figure 27. Example I2C Read Cycle
Table 4. Device Address
Device Address
B7
B6
B5
B4
B3
B2
B1
B0 (R/W)
1
1
0
1
1
1
1
0
Table 5. Mode Selection
SW/HW
SDA/SEL
SCL/GAIN
MODE
0
(Boost Disabled)
0
IN1, AV = 0
1
IN1, AV = 6
1
(Boost Enabled)
0
IN2, AV = 24
1
IN2, AV = 30
X
X
I2C Mode
0
1
8.6 Register Maps
Table 6. I2C Control Registers
REGISTER
ADDRESS
Register
Name
B7
B6
B5
B4
B3
B2
B1
B0
0x00h
SHUTDOWN
CONTROL
X
X
X
X
TURN
_ON
IN_SEL
BOOST
_EN
SHDN
0x01h
NO CLIP
CONTROL
X
RLT1
RLT0
ATK1
ATK0
PLEV2
PLEV1
PLEV0
0x02h
GAIN CONTROL
X
X
X
X
X
X
GAIN1
GAIN0
0x03h
TEST MODE
X
X
X
X
X
X
X
X
Table 7. Shutdown Control Register
BIT
NAME
VALUE
B7:B4
UNUSED
X
Unused, set to 0
0
Normal turn on time, tWU = 15 ms
1
Fast turn on time, tWU = 5 ms
B3
TURN_ON
DESCRIPTION
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
15
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
Table 7. Shutdown Control Register (continued)
BIT
NAME
B2
IN_SEL
B1
BOOST_EN
B0
SHDN
VALUE
DESCRIPTION
0
Input 1 selected
1
Input 2 selected
0
Boost disabled
1
Boost enabled
0
Device shutdown
1
Device enabled
Table 8. No Clip Control Register
BIT
NAME
VALUE
B7
UNUSED
X
RLT1 (B6)
RLT0 (B5)
B6:B5
ATK1 (B4)
ATK0 (B3)
B4:B3
PLEV2 (B2)
PLEV1 (B1)
PLEV0 (B0)
B2:B0
DESCRIPTION
Unused, set to 0
B6
B5
Sets Release Time based on CSET.
See Release Time section.
0
0
TR = 0.5 s
0
1
TR = 0.38 s
1
0
TR = 0.21 s
1
1
TR = 0.17 s
B4
B3
Sets Attack Time based on CSET.
See Attack Time section.
0
0
TA = 0.83 ms
0
1
TA = 1.2 ms
1
0
TA = 1.5 ms
1
1
TA = 2.2 ms
B2
B1
B0
Sets output voltage limit level.
0
0
0
Voltage Limit disabled
0
0
1
VTH(VLIM) = 14 VP-P
0
1
0
VTH(VLIM) = 17 VP-P
0
1
1
VTH(VLIM) = 20 VP-P
1
0
0
VTH(VLIM) = 22 VP-P
1
0
1
VTH(VLIM) = 25 VP-P
1
1
0
VTH(VLIM) = 28 VP-P
1
1
1
Voltage Limit disabled
Table 9. Gain Control Register
BIT
NAME
VALUE
DESCRIPTION
B7:B2
UNUSED
X
Unused, set to 0
B1:B0
B1:B0
16
GAIN1(B1)
GAIN0 (B0)
GAIN1(B1)
GAIN0 (B0)
B1
B0
Sets amplifier gain.
Boost disabled (BOOST_EN = 0)
0
0
0 dB
0
1
6 dB
1
0
12 dB
1
1
18 dB
B1
B0
Sets amplifier gain.
Boost enabled (BOOST_EN = 1)
0
0
21 dB
0
1
24 dB
1
0
27 dB
1
1
30 dB
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
9 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
9.1 Application Information
The LM48560 device is a high voltage, high efficiency Class H driver for ceramic speakers and piezo actuators.
The integrated, high efficiency boost converter dynamically adjusts the amplifier’s supply voltage based on the
output signal to increase headroom and improve efficiency. The LM48560 device’s Class H architecture offers
significant power savings compared to traditional Class AB amplifiers. The device provides 30Vp-p output drive
while consuming just 4 mA of quiescent current from a 3.6 V supply.
The LM48560 device features two fully differential inputs with separate gain settings, and a selectable control
interface. In software control mode, the gain control and device modes are configured through the I2C interface.
In hardware control mode, the gain and input mux are configured through a pair of logic inputs. The LM48560
device has a low current shutdown mode that disables the amplifier and boost converter and reduces quiescent
current consumption to 0.1 μA.
9.2 Typical Application
Figure 28. Demo Board Schematic
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
17
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
Typical Application (continued)
9.2.1 Design Requirements
Table 10 shows the design parameters for this design example.
Table 10. Design Parameters
PARAMETERS
VALUES
Supply voltage
2.7 V to 5.5 V
Temperature
–40 °C to 85 °C
Input voltage
–0.3 V to Vdd 0.3 V
9.2.2 Detailed Design Procedure
9.2.2.1 Proper Selection of External Components
9.2.2.1.1 ALC Timing (CSET) Capacitor Selection
The recommended range value of CSET is between 0.01 μF to 1 μF. Lowering the value below 0.01 μF can
increase the attack time but LM48560 device ALC ability to regulate its output can be disrupted and approaches
the hard limiter circuit. This in turn increases the THD+N and audio quality will be severely affected.
9.2.2.1.2 Power Selection of External Components
Proper power supply bypassing is critical for low noise performance and high PSRR. Place the supply bypass
capacitors as close to the device as possible. Place a 1-µF ceramic capacitor from VDD to GND. Additional bulk
capacitance may be added as required.
9.2.2.1.3 Boost Converter Capacitor Selection
The LM48560 device boost converter requires three external capacitors for proper operation: a 1-μF supply
bypass capacitor, and 1-μF + 100-pF output reservoir capacitors. Place the supply bypass capacitor as close to
VDD as possible. Place the reservoir capacitors as close to VBST and VAMP as possible. Low ESR surfacemount multi-layer ceramic capacitors with X7R or X5R temperature characteristics are recommended. Select
output capacitors with voltage rating of 25 V or higher. Tantalum, OS-CON and aluminum electrolytic capacitors
are not recommended.
9.2.2.1.4 Inductor Selection
The LM48560 device boost converter is designed for use with a 4.7-μH inductor. Choose an inductor with a
saturation current rating greater than the maximum operating peak current of the LM48560 device (> 1A). This
ensures that the inductor does not saturate, preventing excess efficiency loss, over heating and possible damage
to the inductor. Additionally, choose an inductor with the lowest possible DCR (series resistance) to further
minimize efficiency losses.
9.2.2.1.5
Diode Selection
Use a Schottkey diode as shown in Figure 28. A 20-V diode such as the NSR0520V2T1G from On
Semiconductor is recommended. The NSR0520V2T1G is designed to handle a maximum average current of 500
mA.
18
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
9.2.3 Application Curve
Figure 29. Out+, Out– and Vbst Waveforms for a 100 Hz Input Sine Wave
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
19
LM48560
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
www.ti.com
10 Power Supply Recommendations
The LM48560 device is designed be operate with a power supply between 2.7 V and 5.5 V. Proper power supply
bypassing is critical for low noise performance and high PSRR. Place the supply bypass capacitors as close to
the device as possible. Place a 1-μF ceramic capacitor from VDD to GND. Additional bulk capacitance may be
added as required.
11 Layout
11.1 Layout Guidelines
Minimize trace impedance of the power, ground and all output traces for optimum performance. Voltage loss due
to trace resistance between the LM48560 device and the load results in decreased output power and efficiency.
Trace resistance between the power supply and ground has the same effect as a poorly regulated supply,
increased ripple and reduced peak output power. Use wide traces for power supply inputs and amplifier outputs
to minimize losses due to trace resistance, as well as route heat away from the device. Proper grounding
improves audio performance, minimizes crosstalk between channels and prevents switching noise from
interfering with the audio signal. Use of power and ground planes is recommended.
Place all digital components and route digital signal traces as far as possible from analog components and
traces. Do not run digital and analog traces in parallel on the same PCB layer. If digital and analog signal lines
must cross either over or under each other, ensure that they cross in a perpendicular fashion.
11.2 Layout Example
Use wide traces for power supply
inputs and amplifier outputs
Route digital signal traces far
from analog traces
Figure 30. PCB Layout Example
20
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
LM48560
www.ti.com
SNAS513F – AUGUST 2011 – REVISED NOVEMBER 2015
12 Device and Documentation Support
12.1 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
12.2 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
12.3 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
12.4 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
13 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Submit Documentation Feedback
Copyright © 2011–2015, Texas Instruments Incorporated
Product Folder Links: LM48560
21
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LM48560TL/NOPB
ACTIVE
DSBGA
YZR
16
250
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
-40 to 85
GO5
LM48560TLX/NOPB
ACTIVE
DSBGA
YZR
16
3000
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
-40 to 85
GO5
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
工商网监
湘ICP备2023018690号
