LM4545 National Semiconductor, LM4545 Datasheet
LM4545
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LM4545 Summary of contents
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... LM4545 AC ’97 Codec with Stereo Headphone Amplifier and National 3D Sound General Description The LM4545 is an audio codec for PC systems which per- forms the analog-intensive function of the Analog Codec ’97 Rev 1.03 Architecture. Using 18-Bit A/D and D/A convert- ers, the LM4545 provides 90dB of dynamic range. ...
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... L CD 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. 25˚C. The reference A Units LM4545 (Limits) Typical Limit (Note 7) (Note 8) 4.2 V (min) 5.5 V (max) 3.0 V (min) 5.5 V (max 1 ...
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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 3 = 25˚C. The reference A Units LM4545 (Limits) Typical Limit (Note 7) (Note (min) 20 kHz 18 Bits 89 ...
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... DD DD Conditions For cold reset 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 LM4545 resistor 25˚C. The reference A Units LM4545 (Limits) Typical ...
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Timing Diagrams Clocks DS100069-10 Data Setup and Hold DS100069-11 Digital Rise and Fall DS100069-12 Cold Reset DS100069-13 Warm Reset DS100069-14 5 www.national.com ...
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... Typical Application FIGURE 2. LM4545 Typical Application Circuit www.national.com 6 DS100069-3 ...
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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 LM4545VH See NS Package Number VBH48A 7 DS100069-2 www.national.com ...
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Pin Descriptions (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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... This data stream contains both control data and ADC audio data. This output is clocked out SDATA_IN the LM4545 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 DS100069-15 Analog Loopthru Noise Floor DS100069-18 Headphone Amplifier - THD+N vs Frequency DS100069-21 www.national.com DAC Noise Floor DS100069-16 ADC Frequency Response DS100069-19 Headphone Amplifier - THD+N vs Output Power DS100069-22 10 Headphone Amplifier - ...
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11 www.national.com ...
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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 LM4545 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 SD_OUT Slot 2: Control Data Slot 2 is used to transmit 16 bit control data to the LM4545 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 which changes all of the registers back to their default val- ues read is performed on this register, the LM4545 will return a value of 0D50h implying 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 program LM4545 powerdown states. The lower half of this register is read only with a 1 indicated the sub- section is ready. Writing to the lower 8 bits will have no effect. ...
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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 LM4545VH NS Package Number VBH48A 2 ...