LM49450SQ/NOPB National Semiconductor, LM49450SQ/NOPB Datasheet - Page 28

• Manufacturer Part Number: LM49450SQ/NOPB
• Description: IC AUDIO SUBSYSTEM 2.5W D 32LLP
• Manufacturer: National Semiconductor
• Series: Boomer®r
• Type: Class Dr

Specifications of LM49450SQ/NOPB

• Output Type: 2-Channel (Stereo) with Stereo Headphones
• Max Output Power X Channels @ Load: 2.5W x 2 @ 4 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Features: 3D, DAC, Depop, I²C, I²S, Mute, Short-Circuit and Thermal Protection, Shutdown, Volume Control
• Mounting Type: Surface Mount
• Package / Case: 32-LLP
• Amplifier Class: D
• No. Of Channels: 2
• Output Power: 1.2W
• Supply Voltage Range: 2.7V To 5.5V
• Load Impedance: 8ohm
• Operating Temperature Range: -40°C To +85°C
• Amplifier Case Style: LLP
• Rohs Compliant: Yes
• For Use With: LM49450SQEVAL - BOARD EVAL FOR LM49450
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM49450SQ; LM49450SQ; LM49450SQTR

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CHARGE PUMP CLOCK REGISTER (0x02h)
The charge pump clock register sets the charge pump fre-
quency derived from MCLK when the LM49450 is in DAC
mode. Default value is for register 02h is 0x49h.
CP_DIV REGISTER
LM49450 Clock Structure
This register is used to control the charge pump clock when
the register field LINE_IN_ENABLE is low i.e. DAC mode.
Examples of CP_DIV Values one might use for various
sample rates and DAC modes
B7:B0
Bit
CPDIV_7
CPDIV_6
CPDIV_5
CPDIV_4
CPDIV_3
CPDIV_2
CPDIV_1
CPDIV_0
Name
Bits
(B7)
(B6)
(B5)
(B4)
(B3)
(B2)
(B1)
(B0)
7:0
MCLK (MHZ)
2.75625
5.5125
2
3
4
6
8
B7
0
0
0
0
0
0
1
1
1
B6
0
0
0
0
0
0
1
1
1
TABLE 8. Typical CP_DIV Values for DAC Mode 00
CP_DIV
TABLE 6. Charge Pump Clock Register
TABLE 7. CP_DIV Default Value 0x49h
B5
Field
0
0
0
0
0
0
1
1
1
TO
B4
0
0
0
0
0
0
1
1
1
Value
CP_DIV
11
16
17
23
33
36
48
B3
28
0
0
0
0
0
0
1
1
1
Programs the CP divider (devides from an expected 12.000MHz
When the register field LINE_IN_ENABLE is high, the Clocks
module is held in reset and as a result no CP_CLOCK_C is
produced.
B2
0
0
0
0
1
1
1
1
1
CP_DIV
5 to 253
254
255
0
1
2
3
4
B1
0
0
1
1
0
0
0
1
1
Description
B0
0
1
0
1
0
1
1
0
1
input).
Nominal Frequency (Hz)
Sets charge pump oscillator
frequency in DAC mode
(derived from MCLK).
333333
324265
333333
333333
324264
324324
326530
In 0.5 increments
Bypass divider
Divide Value
Description
3 to 127
Bypass
127.5
127.5
128
127
128
1.5
2.5
1.5
2.5
1
2
1
2
3