AKM AK7841

ASAHI KASEI
[AK7841]
AK7841
Monaural Audio Class-D Amp with Power Booster for
PiezoSpeaker
GENERAL DESCRIPTION
The AK7841 is a Monaural Class-D amplifier for driving Piezo-Electric Speakers. Its built-in power boost
DCDC converter generates adequate high voltage for driving Piezo Speaker from a Li-Ion battery.
Output filter-less solution eliminates post LC-filters, which are normally required at Class-D outputs, and
contributes to total space savings. Class-D operation ensures higher power efficiency. The AK7841 is
the most appropriate for Cellular Phones with a piezo speaker.
FEATURES
□ Class-D Amplifier :
• Piezo-Electric Speaker Driver
• Analog Monaural signal input for both single and Differential-ended
• Monaural BTL output
• Output voltage = 12Vpp @VDD1=8.75V
• Filter-less solution
• Pop noise free architecture during power up or down.
• Output short protection
□ Boost DCDC Converter :
• Input voltage = 2.7V ∼ 4.5V Æ Output voltage = 8.75V
• Over-current protection
• Over-voltage protection
□Control function :
• Pre-gain amplifier
−3dB ∼ +18dB, 3dB step.
• Power-own control
• Over-temperature protection
Controlled by pin setting.
□Operational voltage :VBAT=2.7V ∼ 4.5V、DVDDI=1.65V ∼ 4.5V
□Operational temperature:
−30°C ∼ 85°C
□Package: 24pin WL-CSP (2.5mm × 2.5mm, 0.5mm pitch)
Rev.08
2008/3
-1-
ASAHI KASEI
[AK7841]
BLOCK DIAGRAM
DVDDI
PDN
VBAT
PD
C ont
VCO IL
Pow er
Booster
PG 0
Gain
C ontrol
PG 1
VFB
ERRO
VSS2
PG 2
VDD1
INN
C lass-D
AM P
Pre
AM P
-3dB ∼ +18dB
3dB step
INP
VCP
VSS1
+16dB
SDSEL
VC
VCN
VREF
VSS3
Figure. 1 Block Diagram
Rev.08
2008/3
-2-
ASAHI KASEI
[AK7841]
PIN ASSIGNMENT
5
4
3
2
1
E
D
C
B
A
< Top View >
E
D
C
B
A
5
NC
VCOIL
ERRO
PG2
NC
4
VFB
VSS2
VBAT
PG0
PG1
3
2
VDD1
VCP
SDSEL
VCN
NC
VSS3
PDN
INN
DVDDI
<Index>
Figure.2 Pin assignment
Rev.08
1
NC
VSS1
VC
INP
NC
2008/3
-3-
ASAHI KASEI
[AK7841]
Pin / FUNCTION
No.
A1
A2
A3
A4
A5
Pin Name
NC
DVDDI
PG1
NC
I/O
-
B1
INP
I
B2
INN
I
B3
PDN
I
B4
B5
PG0
PG2
I
I
C1
VC
O
C2
C3
C4
VSS3
NC
VBAT
-
C5
ERRO
O
D1
D2
VSS1
VCN
O
D3
SDSEL
I
D4
D5
E1
E2
E3
E4
E5
VSS2
VCOIL
NC
VCP
VDD1
VFB
NC
O
O
I
-
I
-
Function
No Connection pin. * Must be connected to VSS level.
<Index>
Digital interface power:DVDDI=1.65V ∼ 4.5V
Pre Gain setting pin1
No Connection pin. * Must be tied to VSS level during normal usage.
Positive analog input while differential-ended.
OPEN while single-ended input.
Negative analog input while differential-ended.
Analog input while single-ended.
Power down contorol:schmitt trigger input
“High”:poewer up、”Low”:power down
Pre Gain setting pin0
Pre Gain setting pin2
Voltage reference output
* Connect 0.01µF capacitor in between VC and ground.
Internal analog circuit ground pin:VSS3=0V
No Connection pin. * Must be connected to VSS level.
Battery voltage input:VBAT=2.7V ∼ 4.5V
Phase compensation for Boost DCDC.
* Connect 0.1µF capacitor in between ERRO and ground.
Class D amp ground pin :VSS1=0V
Class D amp negative output (-)
single-end/differential input setting pin
“High” : single-end
“Low”: differential input
Power Booster ground pin: VSS2=0V
Inductor pin for Boost DCDC.
No Connection pin. * Must be connected to VSS level.
Class D amp positive output (+)
Class D amp power supply :VDD1=8.75V(typ.)
Power Booster feedback
No Connection pin. * Must be connected to VSS level.
Note 1. Digital input pins (PDN, PG0, PG1, PG2, TEST1, TEST2) and NC pins must not be open.
„ Un-used Pins
Un-used pin must be configured as follows.
Analog
Pin Name
INP
Configuration
OPEN
Rev.08
2008/3
-4-
ASAHI KASEI
[AK7841]
ABSOLUTE MAXIMUM RATINGS
(VSS1=VSS2=VSS3=0V; Note 2)
Parameter
Power Supplies
Battery
Class-D Amp
Digital I/F
|VSS2-VSS1| (Note 3)
|VSS2-VSS3| (Note 3)
Input Current (any pins except for supplies)
Analog Input Voltage(Note 4) (Note 6)
Digital Input Voltage (Note 5) (Note 6)
Ambient Temperature
Storage Temperature
Symbol
VBAT
VDD1
DVDDI
∆GND1
∆GND2
IIN
VINA
VIND
Ta
Tstg
Min.
−0.3
−0.3
−0.3
−0.3
−0.3
−30
−65
Max.
6.5
10
6.5
0.3
0.3
±10
VBAT+0.3
DVDDI+0.3
85
150
Units
V
V
V
V
V
mA
V
V
°C
°C
Note 2. All voltages are with respect to ground.
Note 3. VSS1, VSS2, VSS3 pins must be connected to the same analog ground plane.
Note 4. IPN and INN pin.
Note 5. PDN, PG0, PG1, PG2, SDSEL pin.
Note 6. Maximum value must not exceed 6.5V even if VBAT or DVDDI are more than 6.2V.
WARNING:
Operation at or beyond these limits may result in permanent damage to the device. Normal
operation is not guaranteed at these extremes.
RECOMMENDED OPERATING CONDITIONS
(VSS1=VSS2=VSS3=0V;Note 2)
Parameter
Power Supplies
Battery (Note 7)
Class-D Amp (Note 8)
Digital I/F (Note 7)
Symbol
VBAT
VDD1
DVDDI
Min.
2.7
1.65
Typ.
3.6
8.75
2.8
Max.
4.5
4.5
Unit
V
V
V
Note 7. Have to be “VBAT≧ DVDDI”
Note 8. Supply with boosted voltage (typ. 8.75V) by the Power Booster.
* AKEMD assumes no responsibility for usage beyond the conditions in this datasheet.
Rev.08
2008/3
-5-
ASAHI KASEI
[AK7841]
DC CHARACTERISTICS
(Ta=25°C; VBAT=2.7V ∼ 4.5V, DVDDI=1.65V ∼ 4.5V, VSS1=VSS2=VSS3=0V)
Parameter
Symbol
Min.
Typ.
High-Level Input Voltage 1 (Note 9)
VIH1
70%DVDDI Low-Level Input Voltage 1
(Note 9)
VIL1
High-Level Input Voltage 2 (Note 10)
VIH2
80%DVDDI Low-Level Input Voltage 2
(Note 10)
VIL2
Hysterisys Voltage
DVDDI=2.8V
VHS1
0.5
(Note 10)
DVDDI=1.65V
VHS2
0.3
Input Leakage Current
Iin
-
Max.
30%DVDDI
20%DVDDI
±10
Units
V
V
V
V
V
V
µA
Note 9. Applied to PG0, PG1, PG2, and SDSEL pin.
Note 10. Applied to PDN pin (Summit trigger input. These specifications are guaranteed by design and characterization
and are not tested in production.)
Rev.08
2008/3
-6-
ASAHI KASEI
AKM CONFIDENTIAL
[AK7840]
ANALOG CHARACTERISTICS
(Typ.) value is measured at Ta=25℃ and VBAT=3.6V,. The worst value was measured at the worst point between
VBAT=2.7~4.5V and Ta=-30~+85℃, and written on (Min.) or (Max.) column.
Unless otherwise specified, Ta=25℃, VBAT=3.6V, DVDDI=2.8V, VSS1=VSS2=VSS3=0V;input signal frequency
=1kHz; measurement band width=20Hz ∼ 20kHz; pre gain=0dB; Class-D amp load capacitance is 1.0uF.
Parameter
Conditions
Min.
Typ.
Max.
Units
No input signal
Idd
17.3
26.0
mA
With output load.
Shutdown Current
PDN pin = “Low”
1.0
10
µA
INN pin
25
50
75
kΩ
Input Impedance
INP pin
25
50
75
kΩ
Pre Gain
-3.0
+18.0
dB
Control Range
PG2=”L”, PG1 = “L” , PG0 = “L”
-4.0
-3.0
-2.0
dB
PG2=”L”, PG1 = “L” , PG0 = “H”
-1.0
0.0
+1.0
dB
PG2=”L”, PG1 = “H” , PG0 = “L”
+2.0
+3.0
+4.0
dB
Pre Gain
PG2=”L”, PG1 = “H” , PG0 = “H”
+5.0
+6.0
+7.0
dB
Step Size
PG2=”H”, PG1 = “L” , PG0 = “L”
+8.0
+9.0
+10.0
dB
PG2=”H”, PG1 = “L” , PG0 = “H”
+11.0
+12.0
+13.0
dB
PG2=”H”, PG1 = “H” , PG0 = “L”
+14.0
+15.0
+16.0
dB
PG2=”H”, PG1 = “H” , PG0 = “H”
+17.0
+18.0
+19.0
dB
VCN/VCP pins
Output Voltage
3.82.
4.24
4.66
Vrms
Input signal level=0.70Vrms
THD=10%
VCN/VCP pins
Output Offset Voltage
250
mV
No input signal
VCN/VCP pins
dB
THD+N
−40
Input signal level=0.50Vrms
VCN/VCP pins
SNR
Input signal level=0.70Vrms,
70
80
dB
using A-weighting filter
PSRR
VCN/VCP pins
(Note 12)(Note 1Note
Vripple=200mVpp @1kHz Sine-wave,
65
dB
15)
VBAT=3.6V, all temperature
CMRR
INP=1.2V±0.5V @Sine-wave,
65
dB
(Note 12)(Note 1Note
VBAT=3.6V, all temperature
15)
VREF
VC pin
2.4
V
Output Voltage
(Note 12) (Note 13)
Class-D Amp
225
250
275
kHz
Switching
Frequency
Power Booster
900
1000
1100
kHz
Start-up Time
VBAT=2.7V
28
31
ms
(Note 14)
Note 11. Measure between VCN and VCP pin through Low-Pass-Filter (fc=20kHz).
Note 12. These specifications are guaranteed by design and characterization and are not tested in production.
Note 13. Analog ground in the AK7841 is 1.2V(typ.).
Note 14. Time period that is required to be stable output after PDN is “High”.
Note 15. These specifications are guaranteed by design and characterization and are not tested in production.
Rev.08
2008/3
-7-
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
OPERATION OVERVIEW
„ Power Control
The AK7841 enters shutdown mode by setting “PDN” pin to Logic “Low” level.
And resumes normal operation mode (Stability Operation) by setting “PDN” pin to Logic “High” level.
Power-Up Control
VBAT and DVDDI must be turned on as (1) or (2) below.
(1) VBAT=DVDDI=”ON” simultaneously.
(2) VBAT=”ON” first, then DVDDI=”ON”.
Set PDN pin to “High” when driving AK7841. Then, 1µs wait after VBAT=DVDDI=”High” is necessary
before setting PDN=”High”. Do not do them simultaneously.
VBAT “ON”
0V
DVDDI “ON”
0V
PDN pin
0V
> 1us
Figure. 3 Power-Up Sequence (1)
VBAT “ON”
0V
DVDDI “ON”
0V
0V
PDN pin
0V
>0
> 1us
Figure. 4 Power –Up Sequence (2)
Attention: The performance of the device will not be guaranteed after the below sequence.
(3) DVDDI=”ON” first, then VBAT=”ON”.
Rev.08
2008/3
-8-
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
Power-Down Control
VBAT and DVDDI must be turned off as (4) or (5) below.
(4) VBAT=DVDDI=”OFF” at the same time.
(5) DVDDI=”OFF” first, then VBAT=”OFF”.
Set PDN pin to “Low” when shutting down. Then, 1µs wait is necessary before pulling down VBAT
and DVDDI. Do not do them simultaneously.
※ When PDN pin is “High” and VBAT/DVDDI supply is suddenly cut off due to unexpected event, pop noise may be
detected while sound signal is being output. Even under such cases LSI will not be harmed.
VBAT “OFF”
0V
DVDDI “OFF”
0V
> 1us
PDN pin
0V
Figure. 5 Power-Down Sequence (4)
///VBAT “OFF”
>0
DVDDI “OFF”
0V
0V
> 1us
PDN pin
0V
Figure. 6 Power –Down Sequence (5)
Attention: The performance of the device will not be guaranteed after the below sequence.
(6) VBAT=”OFF” first, then DVDDI=”OFF”
„
Analog inputs
The AK7841 correspond to both single and differential-ended input. Use ac coupling capacitors as described below.
Avoid the change from 0.1uF of the recommended value as much as possible because these change of capacitance
may influence not only HPF (High Pass Filter) at input but also the operation of the pop noise prevention circuit.
When single-ended input
Connect SDSEL pin to ground. Input t analog signal to INN pin through a 0.1uF capacitor. Then, INP pin should
be open. ( Figure. 16)
When differential-ended input
Connect SDSEL pin to DVDDI. Input t analog signal to between INN and INP pins through ac-coupling 0.1uF
capacitors ( Figure. 17). If two conditions are fulfilled as below, ac-coupling capacitors are not needed
( Figure. 18).
1. The voltage of INP and INN are VSS while shutting down.
2. The common level of INP and INN pin is between 0.8V and 1.6V, and input signals are within
common level±0.5V for each pin (2Vpp).
Rev.08
2008/3
-9-
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
„ Pre AMP
Users can change Pre Gain value by setting PG0, PG1, PG2 pins as following Table.1.
For fixed gain application, these pins should be fixed to either VSS3 or DVDDI.
PG2
PG1
PG0
“Low”
“Low”
“Low”
“Low”
“High”
“High”
“High”
“High”
“Low”
“Low”
“Low”
“High”
“High”
“Low”
“High”
“High”
“Low”
“Low”
“Low”
“High”
“High”
“Low”
“High”
“High”
Table.1 Pre Gain setting
Pre Gain Setting
Value
-3.0 dB
0.0 dB
+3.0 dB
+6.0 dB
+9.0 dB
+12.0 dB
+15.0 dB
+18.0 dB
„ Class-D amplifier.
The AK7841, a monaural Class-D audio amplifier, has higher efficiency compared to Class-AB amplifier. AK7841
would eliminate much external equipment especially output filter, which is normally equipped to cut high frequency
spectrum in class-D output, by using a unique circuit composition.
„ Pop Noise Suppressor
The AK7841 features click-and-pop suppression circuit.
„ Power Booster
Built-in BOOST DCDC CONVERTER generates adequate high voltage for Piezo-Speaker (Typ.8.75V) from a
Li-Ion battery voltage range (2.7~4.5V). Supply boosted voltage (VFB=8.75V) to VDD1 for class-D amp operation.
„ Protection
The AK7841 supports following protection circuits for protecting against any damages.
Output Short-Circuit Protection
In case detecting VCL(R)P and VCL(R)N short, the AK7841 clamps peak current of Class-D output circuit
without shutting down the outputs.
Over-Temperature Protection
The AK7841 operation will stop at +150°C.
Note that the AK7841 DOES NOT support resume function from Over-Temperature Protection. Once it is
activated, the AK7841 does not back in normal operation unless “PDN” is toggled (“L” Æ “H”).
Over-Current Protection
Current-limiting protection clamps the output current without shutting down the outputs.
Over-Voltage Protection
AK7841 has a Voltage-limiting protection in DCDC converter to avoid destroying itself.
Rev.08
2008/3
- 10 -
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
Performance characteristics
The following various characteristics are typical characteristic data in the typical condition. It is not the one
necessarily to secure the characteristic of the description.
※
Sinwave Single - ended , Total Gain=15.6dB, Output Load Impedance ZL=1uF,
Measurement Band Width =20~20kz, unless otherwise specified.
10
10
VBAT=3.6
VBAT=4.5V
1
Vout=4Vrms
Vout=4Vrms
THD+N (%)
THD+N (%)
1
Vout=2Vrms
0.1
Vout=2Vrms
Vout=1Vrms
0.1
Vout=1Vrms
0.01
0.01
10
0.01
100
0.1
1k
1
10k
10 20k
100k
100
Frequency (Hz)
10
0.01
100
0.1
1k
1
10k
10 20k
100k
100
Frequency (Hz)
10
VBAT=2.7V
1
THD+N (%)
Vout=4Vrms
Vout=2Vrms
Vout=1Vrms
0.1
0.01
10
0.01
100
0.1
1k
1
10k
10 20k
100k
100
Frequency (Hz)
Figure. 7 Total Harmonic Distortion Plus Noise vs Frequency
Rev.08
2008/3
- 11 -
AKM CONFIDENTIAL
ASAHI KASEI
10
[AK7840]
10
VBAT=3.6V
VBAT=4.5V
Fin=10kHz
THD+N (%)
1
THD+N (%)
1
Fin=4kHz
0.1
Fin=10kHz
Fin=4kHz
Fin=1kHz
0.1
Fin=1kHz
0.01
0.01
0
1
2
3
4
5
0
Output Voltage (Vrms)
1
2
3
4
5
Output Voltage (Vrms)
10
VBAT=2.7V
THD+N (%)
1
Fin=10kHz
Fin=4kHz
Fin=1kHz
0.1
0.01
0
1
2
3
4
5
Output Voltage (Vrms)
Figure. 8 Total Harmonic Distortion Plus Noise vs Output Voltage
Rev.08
2008/3
- 12 -
AKM CONFIDENTIAL
ASAHI KASEI
5
※)Wave forms are overlapping.
20
※)Wave forms are overlapping.
Vout=2Vrms
Vin=2Vpp
VBAT=4.5V
VBAT=4.5V
4
3
VBAT=3.6V
15
VBAT=3.6V
VBAT=2.7V
VBAT=2.7V
Gain (dB)
Output Voltage (Vrms)
[AK7840]
2
10
5
1
0
0.01
10
0.1
100
1
1k
10 20k
10k
100
100k
Frequency (Hz)
0
10
0.01
100
0.1
1k
1
10k
10 20k
100k
100
Frequency (Hz)
Figure. 9 Output Amplitude vs. Frequency
Figure. 10 Frequency Response
150
Fin=1kHz
Supply Current @ Stereo (mA)
VBAT=3.6V
VBAT=2.7V
100
50
VBAT=4.5V
0
0
1
2
3
4
5
Output Voltage (Vrms)
Figure. 11 Supply Current vs Output Voltage
Rev.08
2008/3
- 13 -
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
20
18
Shutdown Current (nA)
16
PDN
2V/div
14
12
10
8
6
Output Waveform
10V/div
4
2
10ms/div
0
2.5
3
3.5
4
4.5
5
Supply Voltage (V)
Figure. 12 Shutdown Current vs Supply Voltage
Figure. 13 Startup Waveform
70
※)Wave forms are overlapping.
Vin=1Vpp
A-Weighted
VBAT=2.7V
60
CMRR (dB)
VBAT=3.6V
50
VBAT=4.5V
40
30
20
0.01
0
0.1
100
1
1k
10
10k 20k
100
100k
Frequency (Hz)
Figure. 14
Common-Mode Rejection Ratio vs Frequency
Rev.08
2008/3
- 14 -
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
LEVEL DIAGRAM
Default gain of AK7841 is +15.6dB. Figure. 15.shows the level diagram of AK7841. Pre Gain value is adjustable by pin
control as specified in Table.1.
Pre
Gain
-3 to +18dB by3dB step
Class-D
Class-D amp gain=15.6dB
[Vpp]
14.0
12.0
10.0
8.0
6.0
4.0
PG=0dB
2.0
PG=+6dB
0.0
Figure. 15 Level Diagram
Rev.08
2008/3
- 15 -
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
TYPICAL APPLICATION CIRCUIT
Li-ion Battery
C1: 10uF
C5: 2.2uF
C6: 0.1uF
ERRO
VFB
Power Booster
C2: 0.1uF
SDSEL
PG0
PG1
PG2
※ Refer to "Pre AMP"
section for details.
C8: 0.1uF
INN
INP
VC
C7: 0.01uF
VBAT
D1
DVDDI
PDN
L1: 1.0uH
VCOIL
C4: 10uF
VSS2
PD
Cont
VDD1
Gain
Cont
Pre
AMP
Class-D
AMP
VCN
VCP
VREF
VSS1
Piezo Speaker
C3: 0.1uF
VSS3
Figure. 16 External Components Examples : Single-ended Input
Li-ion Battery
C1: 10uF
C5: 2.2uF
C6: 0.1uF
ERRO
VFB
VBAT
D1
DVDDI
Power Booster
SDSEL
C2: 0.1uF
L1: 1.0uH
VCOIL
VSS2
PDN
※ Refer to "Pre AMP"
section for details.
C8: 0.1uF
PG0
PG1
PG2
INN
INP
PD
Cont
VDD1
Gain
Cont
Pre
AMP
Class-D
AMP
VCN
VCP
VC
C7: 0.01uF
C4: 10uF
VREF
VSS1
Piezo Speaker
C3: 0.1uF
VSS3
Figure. 17 External Components Examples :
Differential Input with ac coupling capacitors at input
Rev.08
2008/3
- 16 -
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
Li-ion Battery
C1: 10uF
C5: 2.2uF
C6: 0.1uF
ERRO
VFB
L1: 1.0uH
VBAT
D1
DVDDI
Power Booster
SDSEL
C2: 0.1uF
VCOIL
VSS2
PDN
PG0
※ Refer to "Pre AMP" PG1
PG2
section for details.
C8: 0.1uF
INN
INP
PD
Cont
VDD1
Gain
Cont
Pre
AMP
Class-D
AMP
VCN
VCP
VSS2
VC
C7: 0.01uF
C4: 10uF
VREF
VSS1
Piezo Speaker
C3: 0.1uF
VSS3
Figure. 18 External Components Examples : Differential Input, direct Connection ※
※If two conditions are fulfilled as below, ac-coupling capacitors are not needed.
1. The voltage of INP and INN are VSS while shutting down.
2. The common level of INP and INN pin is between 0.8V and 1.6V, and input signals are within common
level±0.5V for each pin (2Vpp).
Rev.08
2008/3
- 17 -
ASAHI KASEI
AKM CONFIDENTIAL
[AK7840]
1. Grounding and Power Supply Decoupling
The AK7841 requires careful attention to power supply and grounding arrangements. Supply VBAT with Battery
Power. VDD1 must be supplied with boosted flat voltage. Connect VSS1, VSS2 and VSS3 to analog ground plane.
System analog and digital ground should be isolated from each other and be connected nearby the power supply pin
on the printed circuit board. Decoupling capacitors should be as close to the power supply pins as possible, with the
small value ceramic capacitor nearby power supply.
2. Voltage Reference
VC pin is the analog common voltage (ground for signals). Insert a 0.01µF ceramic capacitor between VC and VSS3
to eliminate the effects of high frequency noise. This capacitor should be as close to the VC pin as possible. Do not
take out load current from the VC pin. All signals, especially clocks, should be kept away from the VC pin in order to
avoid unwanted coupling.
3. Class-D Outputs
The Class-D outputs are in BTL signal format. Locate the outputs close to the speaker to minimize interconnect
resistance and capacitance to suppress noise. Match the length and pattern of the plus and minus output interconnect.
Keep AK7841 or Class-D outputs away as far away as possible from the devices such as antennas that are sensitive to
high frequency noise.
4. Effect on RF bands
Power Booster or Class-D Outputs may affect high frequency signal while applying to some applications.
Apply previous section (3. Class-D Outputs) in PCB layout.
5. Drivable Piezo Speakers
AK7841 is designed to drive typical piezo speakers but in some cases electric characteristics of the speakers differ by
manufacturers. Feel free to ask us whether your speakers can be driven or not before using them.
Rev.08
2008/3
- 18 -
AKM CONFIDENTIAL
ASAHI KASEI
[AK7840]
PACKAGE
A
0.23
2.46±0.05
0.50
E
0.50
D
C
B
A
0.23
2.46±0.05
B
1
INDEX MARK
2
3
4
5
0.60±0.02
0.25±0.05
0.30±0.05
0.05 M S AB
S
Note:
TheTerminal Pitch means the distances between
the terminal centers.
0.08 S
Figure. 19 Package Dimensions (AK7841)
Rev.08
2008/3
- 19 -
ASAHI KASEI
(c)
MARKING
Market number:“7841”
Date code(four digits)
Y
:Last one digits of Christian year (ex. “2007” Æ “7”)
WW
:Manufactured week
L
:Wafer lot number, which manufactured in same week (“A”, “B”, “C”, ・・・)
Index indication
:”A2” pin location
(a)
(b)
7841
YWWL
(a)
(b)
[AK7841]
(C)
Figure. 20 Package Marking (AK7841)
Rev.08
2008/3
- 20 -
ASAHI KASEI
[AK7841]
IMPORTANT NOTICE
z These products and their specifications are subject to change without notice.
When you consider any use or application of these products, please make inquiries the sales office of Asahi Kasei
EMD Corporation (AKEMD) or authorized distributors as to current status of the products.
z AKEMD assumes no liability for infringement of any patent, intellectual property, or other rights in the application
or use of any information contained herein.
z Any export of these products, or devices or systems containing them, may require an export license or other official
approval under the law and regulations of the country of export pertaining to customs and tariffs, currency exchange,
or strategic materials.
z AKEMD products are neither intended nor authorized for use as critical componentsNote1) in any safety, life support,
or other hazard related device or systemNote2), and AKEMD assumes no responsibility for such use, except for the
use approved with the express written consent by Representative Director of AKEMD. As used here:
Note1) A critical component is one whose failure to function or perform may reasonably be expected to result, whether
directly or indirectly, in the loss of the safety or effectiveness of the device or system containing it, and which must
therefore meet very high standards of performance and reliability.
Note2) A hazard related device or system is one designed or intended for life support or maintenance of safety or for
applications in medicine, aerospace, nuclear energy, or other fields, in which its failure to function or perform may
reasonably be expected to result in loss of life or in significant injury or damage to person or property.
z It is the responsibility of the buyer or distributor of AKEMD products, who distributes, disposes of, or otherwise
places the product with a third party, to notify such third party in advance of the above content and conditions, and
the buyer or distributor agrees to assume any and all responsibility and liability for and hold AKEMD harmless from
any and all claims arising from the use of said product in the absence of such notification.
Rev.08
2008/3
- 21 -