1 ( 8 ) da9118.000 11 may, 2000 mas9118 buzzer dac interface excellent frequency response high efficiency 8 ohms driver serial interface separate voltages at interface and driver description mas9118 is a high performance analog interface for buzzer or small loudspeaker. it employs new circuit structures, which provide a possibility to play high quality speech or music by using low cost buzzer or miniature speaker. the driver has excellent power efficiency due to class-d operation and provides high sound pressure due to balanced outputs. the interface is used as any eight bit dac, just by loading the signal to the input register at regular time intervals. features application excellent frequency response msop package no external components easy to use cellular phones toys block diagram this is preliminary information on a new product under development. micro analog systems oy reserves the right to make any changes without notice. din mclk outp outn vddi vdd vss xcs cclk xreset level shifter dac serial interface driver power-down power- down logic
2 ( 8 ) da9118.000 11 may, 2000 pin configuration pin description pin name pin type function din 1 di data input of the serial interface cclk 2 di clock input of the serial interface xcs 3 di chip select of the serial interface, sets the data sampling frequency vss 4 p ground mclk 5 di master clock input outn 6 ao negative output for the buzzer vdd 7 p positive power supply outp 8 ao positive output for the buzzer xreset 9 di reset and power-down, active low vddi 10 ai input signal high reference voltage din cclk vss mclk vddi xreset outp vdd outn xcs mas9118
3 ( 8 ) da9118.000 11 may, 2000 general description main features the data path of mas9118 consists of level shifters, serial interface, interpolating digital to analog converter (dac) and balanced output driver (h-bridge). mas9118 produces pwm (pulse width modulated) output signal according to the digital input data sourced through din. because of the pwm output (class-d amplifier) there is no need for external capacitors between mas9118 output and load element (no dc voltage at output). the amplifier has excellent power efficiency due to class-d operation. the driver distortion characteristic is load insensitive. the buzzer is driven in an h-bridge. the driver balanced outputs double the voltage, which is advantageous for portable devices with low voltage. the device enters to a power-down mode after power- on reset or when xreset pin is low or when master clock is stopped. even though the device is internally reset at start-up it is recommended to keep xreset low when switching powers on and rise xreset signal up later (a few ms after powers are switched on). output pins (outp, outn) are connected to ground voltage (vss) at power-down mode to prevent some times harmful dc bias at output. interfaces there are level shifters in the input (mclk, cclk, din, xcs). input level shifting provides the possibility to use lower signal levels for device control and higher signal level for buzzer driver, which enables higher voltage to buzzer. the operating voltage of the driving circuit should be connected to vddi, which is a reference level for control signals. the input signal is written into the internal register via the asynchronous serial interface. serial interface consists of an input pin for data (din), chip select pin (xcs) and control clock (cclk). cclk has to be pulsed eight times while xcs is low to shift the data in. the data is shifted into the serial input register when 8 cclk pulses has occurred after xcs falling edge. when the eighth rising edge comes the data is re-synchronized with mclk and passed to the dac. xcs has to be set high before next data can be read in (data read is started by xcs falling edge). input data read is cancelled if xcs is set high before all 8 data bits has been read in, and old data remains to device output. the serial data word length is 8 bits and it is 2-complement with msb first. the data (word) rate (xcs falling edge -frequency), which is the device output sampling frequency, should be in the range of 8 to 80 khz for good audio quality. the master clock (mclk) is used for the on-chip sigma-delta modulator, which truncates the 8-bit input signal to 1-bit representation. the mclk is used as a dac output sampling frequency. to minimize jitter, mclk should be integer multiple of the sampling frequency (xcs frequency). since cclk and mclk are allowed to be asynchronous, double buffering for input data is used to guarantee correct operation in all conditions.
4 ( 8 ) da9118.000 11 may, 2000 absolute maximum ratings parameter symbol conditions min max unit positive supply vdd, vddi 6.0 v negative supply vss -0.3 v voltage at any digital input vss-1 to vcc+1 v storage temperature -65 +150 o c esd protection 2000 v latch-up current 100 ma note: short circuit connection between outp/outn pins may destroy the device. recommended operation conditions parameter symbol conditions min typ max unit positive supply vdd 2.5 3.6 5.5 v voltage of the input signal vddi 1.5 1.8 vdd v ambient temperature ta -40 +85 o c standby current istby no load, zero input 1.0 5.0 ma active current idd 8 ohm load, din=1 khz 0db sine vdd=2.5v vdd=3.6v vdd=5.5v tbd 86 142 240 tbd ma ma ma power down leakage current, ext. reset ipd1 xreset=low, mclk active 21 100 a power down leakage current, clock reset ipd2 mclk=low 0.1 a master clock frequency fmclk 0.5 1 3 mhz electrical characteristics u analog characteristics ac characteristics amplitude response (vdd=+3.6v, vddi=+1.8v, vss=0v, f xcs =62.5khz, f mclk =1000khz, f cclk =1000 khz, ta=+25 o c unless otherwise noted) parameter symbol conditions min typ max unit absolute gain error at 1 khz gabs 0.1 db gain variation with frequency gaf relative to gabs, f=0?8khz 0.01 db gain variation with signal level gal relative to gabs 0?-12db 0.5 db gain variation with temperature gat 0.01 db
5 ( 8 ) da9118.000 11 may, 2000 electrical characteristics phase response (vdd=+3.6v, vddi=+1.8v, vss=0v, f xcs =62.5khz, f mclk =1000khz, f cclk =1000 khz, ta=+25 o c unless otherwise noted) parameter symbol conditions min typ max unit absolute group delay gda f=1.0 khz, from rising edge of xcs or 8 th cclk 2 s group delay distortion gdr f=0?20khz, relative to gda 0 ms noise and distortion (vdd=+3.6v, vddi=+1.8v, vss=0v, f xcs =62.5khz, f mclk =1000khz, f cclk =1000 khz, ta=+25 o c unless otherwise noted) parameter symbol conditions min typ max unit signal to noise and distortion ratio snr f=1khz, a-weight 100 kohm load: din=-1db din=-3db din=-6db 8 ohm load: din=-1db din=-3db din=-6db 45 46 47 42 43 44 db db db db db db serial interface timing characteristics parameter symbol conditions min typ max unit frequency of cclk fcclk 13 mhz period of cclk high twhc measured from vih to vih 35 ns period of cclk low twlc measured from vil to vil 35 ns rise time of cclk trc measured from vil to vih 10 ns fall time of cclk tfc measured from vih to vil 10 ns hold time, cclk high to xcs low thcsh 10 ns setup time, xcs low to cclk high tsslch 20 ns setup time, valid din to cclk high tsdch 5 ns hold time, cclk high to invalid ci thchd 10 ns hold time, 8 th cclk high to xcs high thlchs 15 ns 1 2 3 4 5 6 7 8 7 6 5 4 3 2 1 0 twhc trc tfc thcsh tsdch thchd cclk xcs din thlchs twlc tsslch
6 ( 8 ) da9118.000 11 may, 2000 electrical characteristics u digital characteristics dc characteristics (vdd=+3.6v, vddi=+1.8v, vss=0v, f xcs =62.5khz, f mclk =1000khz, f cclk =1000 khz, ta=+25 o c unless otherwise noted) parameter symbol conditions min typ max unit input low voltage vil all digital inputs, dc -0.3 0.3* vddi v input high voltage vih all digital inputs, dc 0.7* vddi v input low current il any digital input, gnd8 ohm 0.5...3 mhz high current routing vbat=2.5...5.5 v regulator in out gnd + >1.5 v battery
7 ( 8 ) da9118.000 11 may, 2000 package (msop10) outlines dimension min typical max unit a 0.95 1.00 1.10 mm a1 0.05 0.10 0.15 mm d 2.90 3.00 3.10 mm e 4.75 4.90 5.05 mm e1 2.90 3.00 3.10 mm t2 0.33 0.41 0.49 mm b 0.15 0.23 0.30 mm l1 0.95 bsc e 0.50 bsc s 0.50 bsc dimensions are in accordance with jedec standard mo-187 (excluding pitch). e s e1 a1 d a b e t2 l1
8 ( 8 ) da9118.000 11 may, 2000 ordering information product code product package comments MAS9118ASMB-T buzzer dac interface msop10 tape and reel local distributor micro analog systems oy contacts micro analog systems oy kamreerintie 2, p.o.box 51 fin-02771 espoo, finland http:\\www.mas-oy.com tel. (09) 80 521 tel. int. +358 9 80 521 telefax +358 9 805 3213 email: i nf o @mas-oy.com notice micro analog systems oy reserves the right to make changes to the products contained in this data sheet in order to improve the design or performance and to supply the best possible products. micro analog systems oy assumes no responsibility for the use of any circuits shown in this data sheet, conveys no license under any patent or other rights unless otherwise specified in this data sheet, and makes no claim that the circuits are free from patent infringement. applications for any devices shown in this data sheet are for illustration only and micro analog systems oy makes no claim or warranty that such applications will be suitable for the use specified without further testing or modification.
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