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Electrical Characteristics
(Notes 2, 3) (Continued)
The following specifications apply for V
DD
= 3.3V unless otherwise specified, limits apply to T
A
= 25C.
Symbol
Parameter
Conditions
LM4809
Units
(Limits)
Typ
(Note 5)
70
Limit
(Note 7)
PSRR
Power Supply Rejection Ratio
C
B
= 1.0μF; V
RIPPLE
= 200mV
PP
,
f = 1kHz; Input terminated into 50
dB
V
SDIH
V
SDIL
Shutdown Voltage Input High
Shutdown Voltage Input Low
0.8 x V
DD
0.2 x V
DD
V (min)
V (max)
Electrical Characteristics
(Notes 2, 3)
The following specifications apply for V
DD
= 2.6V unless otherwise specified, limits apply to T
A
= 25C.
Symbol
Parameter
Conditions
LM4809
Units
(Limits)
Typ
(Note 5)
0.9
0.2
4.0
Limit
(Note 7)
I
DD
I
SD
V
OS
P
O
Supply Current
Shutdown Current
Output Offset Voltage
Output Power
V
IN
= 0V, I
O
= 0A
V
IN
= 0V, V
SHUTDOWN
= GND
V
IN
= 0V
THD+N = 0.1%, f = 1kHz
R
L
= 16
R
L
= 32
P
O
= 15mW, R
L
= 32
f = 20Hz to 20kHz
R
L
= 32
; P
O
= 15mW
C
B
= 1.0μF; V
RIPPLE
= 200mV
PP
,
f = 1kHz; Input terminated into 50
mA
μA
mV
20
16
0.6
mW
mW
%
THD+N
Total Harmonic Distortion
Crosstalk
PSRR
Channel Separation
Power Supply Rejection Ratio
70
70
dB
dB
V
SDIH
V
SDIL
Shutdown Voltage Input High
Shutdown Voltage Input Low
0.8 x V
DD
0.2 x V
DD
V (min)
V (max)
Note 2:
Absolute Maximum Ratings
indicate limits beyond which damage to the device may occur.
Note 3:
All voltages are measured with respect to the ground pin, unless otherwise specified.
Note 4:
Human body model, 100pF discharged through a 1.5k
resistor.
Note 5:
Typical specifications are specified at +25OC and represent the most likely parametric norm.
Note 6:
Tested limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 7:
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Note 8:
Machine Model ESD test is covered by specification EIAJ IC-121-1981. A 200pF cap is charged to the specified voltage, then discharged directly into the
IC with no external series resistor (resistance of discharge path must be under 50Ohms).
Note 9:
The given
θ
is for an LM4809 packaged in an LDA08B wit the Exposed-Dap soldered to a printed circuit board copper pad with an area equivalent to that
of the Exposed-Dap itself.
Note 10:
The given
θ
JA
is for an LM4809 packaged in an LDA08B with the Exposed-Dap not soldered to any printed circuit board copper.
External Components Description
(
Figure 1
)
Components
Functional Description
1. R
i
The inverting input resistance, along with R
f
, set the closed-loop gain. R
i
, along with C
i
, form a high
pass filter with f
c
= 1/(2
π
R
i
C
i
).
The input coupling capacitor blocks DC voltage at the amplifier’s input terminals. C
i
, along with R
i
,
create a highpass filter with f
C
= 1/(2
π
R
i
C
i
). Refer to the section,
Selecting Proper External
Components
, for an explanation of determining the value of C
i
.
The feedback resistance, along with R
i
, set closed-loop gain.
This is the supply bypass capacitor. It provides power supply filtering. Refer to the
Application
Information
section for proper placement and selection of the supply bypass capacitor.
This is the BYPASS pin capacitor. It provides half-supply filtering. Refer to the section,
Selecting
Proper External Components
, for information concerning proper placement and selection of C
B
.
This is the output coupling capacitor. It blocks the DC voltage at the amplifier’s output and forms a high
pass filter with R
L
at f
O
= 1/(2
π
R
L
C
O
)
2. C
i
3. R
f
4. C
S
5. C
B
6. C
O
L
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