lm4547 National Semiconductor Corporation, lm4547 Datasheet
lm4547
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lm4547 Summary of contents
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... LM4547 AC ’97 Rev 2 Codec with National 3D Sound General Description The LM4547 is an audio codec for PC systems which is fully PC98 compliant and performs the analog intensive functions of the AC97 Rev 2 architecture. Using 18-bit Sigma-Delta A/D’s and D/A’s, the LM4547 provides 90dB of Dynamic Range ...
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... R = 10k Left to Right CD Left to Right 0dB to 22.5dB +12dB to -34.5dB 2 215˚C 220˚C 74˚C/W −40˚C T 85˚C MAX A 4.2V AV 5.5V DD 3.0V DV 5.5V DD Units LM4547 (Limits) Typical Limit (Note 7) (Note 8) 4.2 V (min) 5.5 V (max) 3.0 V (min) 5.5 V (max 500 µA 30 µA 2.23 V ...
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... SDATA_IN, SDATA_OUT to falling edge of BIT_CLK Hold time of SDATA_IN, SDATA_OUT from falling edge of BIT_CLK BIT_CLK, SYNC, SDATA_IN or SDATA_OUT BIT_CLK, SYNC, SDATA_IN or SDATA_OUT For cold reset For cold reset 3 Units LM4547 (Limits) Typical Limit (Note 7) (Note (min) 20 kHz 18 Bits ...
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... Limits apply DD DD Conditions For warm reset For warm reset For ATE Test Mode For ATE Test Mode JMAX or the number given in Absolute Maximum Ratings, whichever is lower. For the LM4547 resistor. 4 Units LM4547 (Limits) Typical Limit ...
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Timing Diagrams Clocks DS101029-10 Data Setup and Hold DS101029-11 Digital Rise and Fall DS101029-12 Cold Reset DS101029-13 Warm Reset DS101029-14 5 www.national.com ...
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... Typical Application FIGURE 2. LM4547 Typical Application Circuit www.national.com 6 DS101029-3 ...
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... The amount of AUX_L AUX_L 14 I signal mixed in the left output stream can be adjusted from +12dB to −34.5dB in 1.5dB steps as well as muted via register 16h. Top View Order Number LM4547VH See NS Package Number VBH48A 7 DS101029-2 www.national.com ...
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Pin Description (Continued) Analog I/O (Continued) Name Pin Functional Description This line level input can be routed through the Input Mux and recorded by the right ADC. In addition, this analog input gets summed into the right ...
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... Codec. This data stream contains both status data and ADC audio data. This output is clocked out SDATA_IN the LM4547 on the rising edge of BIT_CLK. 48kHz sync pulse which signifies the beginning of both the SDATA_IN and SDATA_OUT SYNC 10 I serial streams. SYNC must be synchronous to BIT_CLK. ...
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Typical Performance Characteristics ADC Noise Floor DS101029-15 ADC Frequency Response DS101029-19 www.national.com DAC Noise Floor DS101029-16 DAC Frequency Response DS101029-20 10 Analog Loopthru Noise Floor DS101029-18 True Line Level Out Noise Floor (Analog Loopthru) DS101029-18 ...
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... The first bit of slot 0 is designated the Valid Frame bit. If this bit indicates that the current data frame contains at least one slot of valid data and the LM4547 will further sample the next four bits to determine which frames do in fact have valid data. Valid slots are signified their re- spective slot bit position ...
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... Reserved Set to 0 SDATA_OUT Slot 2: Control Data Slot 2 is used to transmit 16 bit control data to the LM4547 in the event that the current operation is a write operation. The least significant four bits should be stuffed with zeros by the AC ’97 controller. If the current operation is a register read, the entire slot, bits 19 through 0 should be stuffed with zeros ...
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... Writing any value to this register causes a register reset returned. which changes all of the registers back to their default val- ues read is performed on this register, the LM4547 will return a value of 0D50h indicating that National 3D Sound is implemented, 18bit data is supported for both the ADC’s and DAC’ ...
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... ADC/DAC loopback Powerdown Control / Status Register (26h) This read/write register is used to monitor subsystem readi- ness and also to program the LM4547 powerdown states. The lower half of this register is read only with indicat- ing the subsection is ready. Writing to the lower 8 bits will have no effect ...
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... Application Information Extended Audio ID Register (28h) This read only register identifies which AC ’97 Extended Au- dio features are supported. The LM4547 provides support for Multiple Codec systems. The two MSB’s, ID1 and ID0, show the current codec configuration as connected via external pins 45 and 46 ...
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... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. 48-Lead , TQFP 1.4mm, JEDEC (M) Order Number LM4547VH NS Package Number VBH48A 2 ...