AK7841 Datasheet, PDF (7/21 Pages) Asahi Kasei Microsystems – Monaural Audio Class-D Amp with Power Booster for PiezoSpeaker

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
Idd
No input signal
With output load.
-
17.3 26.0 mA
Shutdown Current
PDN pin = “Low”
-
1.0
10
µA
Input Impedance
INN pin
INP pin
25
50
75
kΩ
25
50
75
kΩ
Pre Gain
Control Range
-3.0
+18.0 dB
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
Pre Gain
Step Size
PG2=”L”, PG1 = “H” , PG0 = “L”
PG2=”L”, PG1 = “H” , PG0 = “H”
PG2=”H”, PG1 = “L” , PG0 = “L”
+2.0
+3.0 +4.0 dB
+5.0
+6.0 +7.0 dB
+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
Input signal level=0.70Vrms
3.82.
4.24 4.66 Vrms
THD=10%
Output Offset Voltage
VCN/VCP pins
No input signal
-
-
250 mV
THD+N
VCN/VCP pins
Input signal level=0.50Vrms
-
-
−40 dB
VCN/VCP pins
SNR
Input signal level=0.70Vrms,
70
80
-
dB
using A-weighting filter
PSRR
VCN/VCP pins
(Note 12)(Note 1Note
15)
V_ripple=200mVpp @1kHz Sine-wave,
VBAT=3.6V, all temperature
-
65
-
dB
CMRR
(Note 12)(Note 1Note
15)
INP=1.2V±0.5V @Sine-wave,
VBAT=3.6V, all temperature
-
65
-
dB
VREF
Output Voltage
VC pin
-
2.4
-
V
(Note 12) (Note 13)
Switching
Class-D Amp
225
250
275 kHz
Frequency
Power Booster
900
1000 1100 kHz
Start-up Time
(Note 14)
VBAT=2.7V
-
28
31
ms
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-