LM4548AVH National Semiconductor, LM4548AVH Datasheet - Page 13

• Manufacturer Part Number: LM4548AVH
• Manufacturer: National Semiconductor

Specifications of LM4548AVH

• Single Supply Voltage (typ): 3.3/5V
• Single Supply Voltage (min): 3/4.2V
• Single Supply Voltage (max): 5.5V
• Package Type: LQFP
• Lead Free Status / RoHS Status: Not Compliant

Pin Descriptions
V
3DP, 3DN
RESET#
DV
DV
REF_OUT
DV
DV
Name
Name
Name
AV
AV
ID0#
ID1#
V
NC
REF
DD1
DD2
SS1
SS2
DD
SS
44, 47,
29, 30
31, 32
38, 40
42, 43
33,34
Pin
Pin
Pin
11
45
46
25
26
27
28
48
1
9
4
7
I / O
I / O
I / O
NC
O
O
O
I
I
I
I
I
I
I
I
I
(Continued)
Cold Reset
This active low signal causes a hardware reset which returns the control registers and all
internal circuits to their default conditions. RESET# must be used to initialize the LM4548A
after Power On when the supplies have stabilized. Cold Reset also clears the codec from
both ATE and Vendor test modes. In addition, while active, it switches the PC_BEEP mono
input directly to both channels of the LINE_OUT stereo output.
Codec Identity
ID1# and ID0# determine the Codec Identity for multiple codec use. The Codec Identity
configures the codec in either Primary or one of three Secondary Codec modes. These
Identity pins are of inverted polarity relative to the Codec Identity bits ID1, ID0 (bits D15, D14)
in the read-only Extended Audio ID register, 28h. If the ID0# pin (pin 45) is connected to
ground then the ID0 bit (D14, reg 28h) will be set to “1”. Similarly, connection to DV
the ID0 bit to “0”. If left open (NC), ID0# is pulled High by an internal pull-up resistor.
Codec Identity
ID1# and ID0# determine the Codec Identity for multiple codec use. The Codec Identity
configures the codec in either Primary or one of three Secondary Codec modes. These
Identity pins are of inverted polarity relative to the Codec Identity bits ID1, ID0 (bits D15, D14)
in the read-only Extended Audio ID register, 28h. If the ID01# pin (pin 46) is connected to
ground then the ID1 bit (D15, reg 28h) will be set to “1”. Similarly, connection to DV
the ID1 bit to “0”. If left open (NC), ID1 is pulled high by an internal pull-up resistor.
Analog supply
Analog ground
Digital supply
Digital supply
Digital ground
Digital ground
Nominal 2.2 V internal reference
Not intended to sink or source current. Use short traces to bypass (3.3 µF, 0.1 µF) this pin to
maximize codec performance. This pin must be tied to AV
Nominal 2.2 V reference output
Can source up to 5 mA of current and can be used to bias a microphone.
These pins are used to complete the National 3D Sound stereo enhancement circuit. Connect
a 0.022 µF capacitor between pins 3DP and 3DN. National 3D Sound can be turned on and
off via the 3D bit (D13) in the General Purpose register, 20h. National 3D Sound uses a
fixed-depth type stereo enhancement circuit hence the 3D Control register, 22h is read-only
and is not programmable. If National 3D Sound is not needed, these pins should be left open
(NC).
These pins are not used and should be left open (NC).
For second source applications these pins may be connected to a noise-free supply or
ground (e.g. AV
DIGITAL I/O AND CLOCKING (Continued)
POWER SUPPLIES AND REFERENCES
3D SOUND AND NO-CONNECTS (NC)
DD
or AV
SS
), either directly or through a capacitor.
13
Functional Description
Functional Description
Functional Description
DD
with a 10 kΩ pull-up resistor.
www.national.com
DD
DD
will set
will set