MC34119 LOW POWER AUDIO AMPLIFIER

Size: px

Start display at page:

Download "MC34119 LOW POWER AUDIO AMPLIFIER"

Tracy Lucas Gray
6 years ago
Views:

1 Order this document by MC349/D The MC349 is a low power audio amplifier intergrated circuit intended (primarily) for telephone applications, such as in speakerphones. It provides differential speaker outputs to maximize output swing at low supply voltages (2. V minimum). Coupling capacitors to the speaker are not required. Open loop gain is db, and the closed loop gain is set with two external resistors. A Chip Disable pin permits powering down and/or muting the input signal. The MC349 is available in standard pin DIP, SOIC package, and TSSOP package. Wide Operating Supply Voltage Range (2. V to 6 V), Allows Telephone Line Powered Applications Low Quiescent Supply Current (2.7 ma Typ) for Battery Powered Applications Chip Disable Input to Power Down the IC Low PowerDown Quiescent Current (6 µa Typ) Drives a Wide Range of Speaker Loads (. Ω and Up) Output Power Exceeds 2 mw with 32 Ω Speaker Low Total Harmonic Distortion (.% Typ) Gain Adjustable from < db to >46 db for Voice Band Requires Few External Components MAXIMUM RATINGS Rating Value Unit Supply Voltage. to Vdc Maximum Output Current at VO, VO2 ±2 ma Maximum Vin, FC, FC2, CD Applied Output Voltage to VO, VO2 when disabled., VCC.., VCC. Junction Temperature, 4 C NOTE: ESD data available upon request. Vdc LOW POWER AUDIO AMPLIFIER SEMICONDUCTOR TECHNICAL DATA P SUFFIX PLASTIC PACKAGE CASE 626 D SUFFIX PLASTIC PACKAGE CASE 7 (SO) DTB SUFFIX PLASTIC PACKAGE CASE 94J (TSSOP) Block Diagram and Simplified Application PIN CONNECTIONS Rf 7 k CD VO2 6 V CC FC2 2 7 Gnd Audio Input C i. C. µf R i 3. k V in 4 FC 3 C2*. µf FC2 * = Optional Differential Gian = 2 x MOTOROLA ANALOG IC DEVICE DATA 2 Rf Ri k 2 k k # MC k 4. k 7 #2 Gnd Bias Circuit V O V O2 CD Speaker Chip Disable This device contains 4 active transistors. Device MC349P MC349D MC349DTB FC Vin 3 4 (Top View) ORDERING INFORMATION Operating Temperature Range 6 TA = 2 to 7 C VCC VO Package Plastic DIP SO TSSOP Motorola, Inc. 996 Rev

2 RECOMMENDED OPERATING CONDITIONS MC349 Characteristics Symbol Min Max Unit Supply Voltage VCC 2. 6 Vdc CD (Pin ) VCD VCC Vdc Load Impedance RL. Ω Peak Load Current IL ±2 ma Differential Gain (. khz Bandwidth) AVD 46 db Ambient Temperature TA 2 7 C ELECTRICAL CHARACTERISTICS (TA = 2 C, unless otherwise noted.) Characteristics Symbol Min Typ Max Unit AMPLIFIERS (AC CHARACTERISTICS) AC Input Resistance (@ VIn) ri >3 MΩ Open Loop Gain (Amplifier #, f < Hz) AVOL db Closed Loop Gain (Amplifier #2, VCC = 6. V, f =. khz, RL = 32 Ω) AV2.3.3 db Gain Bandwidth Product GBW. MHz Output Power; VCC = 3. V, RL = 6 Ω, THD % POut3 VCC = 6. V, RL = 32 Ω, THD % POut6 2 VCC = 2 V, RL = Ω, THD % POut2 4 Total Harmonic Distortion (f =. khz) THD % (VCC = 6. V, RL = 32 Ω, Pout = 2 mw).. (VCC 3. V, RL =. Ω, Pout = 2 mw). (VCC 2 V, RL = 32 Ω, Pout = 2 mw).6 Power Supply Rejection (VCC = 6. V, VCC = 3. V) PSRR db (C =, C2 =. µf) (C =. µf, C2 =, f =. khz) 2 (C =. µf, C2 =. µf, f =. khz) 2 Differential Muting (VCC = 6. V,. khz f 2 khz, CD = 2. V) GMT >7 db AMPLIFIERS (DC CHARACTERISTICS) Output DC VO, VO2, VCC = 3. V, RL = 6 (Rf = 7 k) VO(3)...2 Vdc VCC = 6. V VO(6) 2.6 VCC = 2 V VO(2).6 Output Level High (Iout = 7 ma, 2. V VCC 6 V) VOH VCC. Low (Iout = 7 ma, 2. V VCC 6 V) VOL.6 Output DC Offset Voltage (VOVO2) VO mv (VCC = 6. V, Rf = 7 kω, RL = 32 Ω) 3 3 Input Bias Vin (VCC = 6. V) IIB 2 na Equivalent FC (VCC = 6. V) RFC FC2 (VCC = 6. V) RFC2 2 4 CHIP DISABLE (Pin ) Input Voltage Low VIL. High VIH 2. Input Resistance (VCC = VCD = 6 V) RCD 9 7 kω POWER SUPPLY Power Supply Current (VCC = 3. V, RL =, CD =. V) ICC ma (VCC= 6 V, RL =, CD =. V) ICC ma (VCC = 3. V, RL =, CD = 2. V) ICCD 6 µa NOTE: Currents into a pin are positive, currents out of a pin are negative. mw Vdc kω Vdc 2 MOTOROLA ANALOG IC DEVICE DATA

3 MC349 PIN FUNCTION DESCRIPTION Symbol Pin Description CD Chip Disable Digital input. A Logic (<. V) sets normal operation. A logic ( 2. V) sets the power down mode. Input impedance is nominally 9 kω. FC2 2 A capacitor at this pin increases power supply rejection, and affects turnon time. This pin can be left open if the capacitor at FC is sufficient. FC 3 Analog ground for the amplifiers. A. µf capacitor at this pin (with a. µf capacitor at Pin 2) provides (typically) 2 db of power supply rejection. Turnon time of the circuit is affected by the capacitor on this pin. This pin can be used as an alternate input. Vin 4 Amplifier input. The input capacitor and resistor set low frequency rolloff and input impedance. The feedback resistor is connected to this pin and VO. VO Amplifier Output #. The dc level is (VCC.7 V)/2. VCC 6 DC supply voltage (2. V to 6 V) is applied to this pin. GND 7 Ground pin for the entire circuit. VO2 Amplifier Output #2. This signal is equal in amplitude, but outofphase with that at VO. The dc level is (VCC.7 V)/2. TYPICAL TEMPERATURE PERFORMANCE (2 C < TA < 7 C) Function Typical Change Units Input Bias Current (@ Vin) ±4 pa/ C Total Harmonic Distortion.3 %/ C (VCC = 6. V, RL = 32 Ω. Pout = 2 mw, f =. khz) Power Supply Current (VCC = 3. V, RL =, CD = V) 2. (VCC = 3. V, RL =, CD = 2. V).3 µa/ C MOTOROLA ANALOG IC DEVICE DATA 3

4 General The MC349 is a low power audio amplifier capable of low voltage operation (VCC = 2. V minimum) such as that encountered in linepowered speakerphones. The circuit provides a differential output (VOVO2) to the speaker to maximize the available voltage swing at low voltages. The differential gain is set by two external resistors. Pins FC and FC2 allow controlling the amount of power supply and noise rejection, as well as providing alternate inputs to the amplifiers. The CD pin permits powering down the IC for muting purposes and to conserve power. Amplifiers Referring to the block diagram, the internal configuration consists of two identical operational amplifiers. Amplifier # has an open loop gain of db (at f Hz), and the closed loop gain is set by external resistor Rf and Ri. The amplifier is unity gain stable, and has a unity gain frequency of approximately. MHz. In order to adequately cover the telephone voice band (3 Hz to 34 Hz), a maximum closed loop gain of 46 is recommended. Amplifier #2 is internally set to a gain of. ( db). The outputs of both amplifiers are capable of sourcing and sinking a peak current of 2 ma. The outputs can typically swing to within.4 V above ground, and to within.3 V below VCC, at the maximum current. See Figures and 9 for VOH and VOL curves. The output dc offset voltage (VOVO2) is primarily a function of the feedback resistor (Rf), and secondarily due to the amplifiers input offset voltages. The input offset voltage of the two amplifiers will generally be similar for a particular IC, and therefore nearly cancel each other at the outputs. Amplifier # s bias current, however, flows out of Vin (Pin 4) and through Rf, forcing VO to shift negative by an amount equal to [Rf IIB]. VO2 is shifted positive an equal amount. The output offset voltage, specified in the Electrical Characteristics, is measured with the feedback resistor shown in the Typical Application Circuit, and therefore takes into account the bias current as well as internal offset voltages of the amplifiers. The bias current is constant with respect to VCC. FC and FC2 Power supply rejection is provided by the capacitors (C and C2 in the Typical Application Circuit) at FC and FC2. C2 is somewhat dominant at low frequencies, while C is dominant at high frequencies, as shown in the graphs of Figures 4 to 7. The required values of C and C2 depend on the conditions of each application. A line powered speakerphone, for example, will require more filtering than a circuit powered by a well regulated power supply. The amount of rejection is a function of the capacitors, and the equivalent impedance looking into FC and FC2 (listed in the Electrical Characteristics as RFC and RFC2). In addition to providing filtering, C and C2 also affect the turnon time of the circuit at powerup, since the two capacitors must charge up through the internal k and 2 kω resistors. The graph of Figure indicates the turnon time upon application of VCC of 6. V. The turnon time is 6% longer for VCC = 3. V, and 2% less for VCC = 9. V. Turnoff time is < µs upon removal of VCC. MC349 DESIGN GUIDELINES t, TURNON TIME (ms) Figure. TurnOn Time versus C, C2 at PowerOn C =. µf 2 C =. µf 6 VCC switching from V to 6. V C2, CAPACITANCE (µf) Chip Disable The Chip Disable (Pin ) can be used to power down the IC to conserve power, or for muting, or both. When at a Logic ( V to. V), the MC349 is enabled for normal operation. When Pin is at a Logic (2. V to VCC V), the IC is disabled. If Pin is open, that is equivalent to a Logic, although good design practice dictates that an input should never be left open. Input impedance at Pin is a nominal 9 kω. The power supply current (when disabled) is shown in Figure. Muting, defined as the change in differential gain from normal operation to muted operation, is in excess of 7 db. The turnoff time of the audio output, from the application of the CD signal, is <2. µs, and turn ontime is 2 ms ms. Both times are independent of C, C2, and VCC. When the MC349 is disabled, the voltages at FC and FC2 do not change as they are powered from VCC. The outputs, VO and VO2, change to a high impedance condition, removing the signal from the speaker. If signals from other sources are to be applied to the outputs (while disabled), they must be within the range of VCC and Ground. Power Dissipation Figures to indicate the device dissipation (within the IC) for various combinations of VCC, RL, and load power. The maximum power which can safely be dissipated within the MC349 is found from the following equation: PD = (4 C TA)/θJA where TA is the ambient temperature; and θja is the package thermal resistance ( C/W for the standard DIP package, and C/W for the surface mount package.) The power dissipated within the MC349, in a given application, is found from the following equation: PD = (VCC x ICC) (IRMS x VCC) (RL x IRMS 2 ) where ICC is obtained from Figure ; and IRMS is the RMS current at the load; and RL is the load resistance. Figures to, along with Figures to 3 (distortion curves), and a peak working load current of ±2 ma, define the operating range for the MC349. The operating range is further defined in terms of allowable load power in Figure 4 for loads of. Ω, 6 Ω and 32 Ω. The left (ascending) portion 4 MOTOROLA ANALOG IC DEVICE DATA

5 of each of the three curves is defined by the power level at which % distortion occurs. The center flat portion of each curve is defined by the maximum output current capability of the MC349. The right (descending) portion of each curve is defined by the maximum internal power dissipation of the IC at 2 C. At higher ambient temperatures, the maximum load power must be reduced according to the above equations. Operating the device beyond the current and junction temperature limits will degrade long term reliability. MC349 Layout Considerations Normally a snubber is not needed at the output of the MC349, unlike many other audio amplifiers. However, the PC board layout, stray capacitances, and the manner in which the speaker wires are configured, may dictate otherwise. Generally, the speaker wires should be twisted tightly, and not more than a few inches in length. A VOL (db) Figure 2. Amplifier # Open Loop Gain and Phase 36 Phase Gain φ, EXCESS PHASE (DEGREES) DIFFERENTIAL GAIN (db) Figure 3. Differential Gain versus Frequency Rf = k, Ri = 6. k Rf = 7 k, Ri = 3. k Input. R i # #2 R f V O V O2 V O. k k k. M. k k 2 k MOTOROLA ANALOG IC DEVICE DATA

6 MC349 PSRR, POWER SUPPLY REJECTION (db) Figure 4. Power Supply Rejection versus Frequency (C2 = µf) 6 C. µf C =. µf C = 2. k k 2 k PSRR, POWER SUPPLY REJECTION (db) Figure. Power Supply Rejection versus Frequency (C2 =. µf) 6 C. µf C =. µf C = 2. k k 2 k PSRR, POWER SUPPLY REJECTION (db) Figure 6. Power Supply Rejection versus Frequency (C2 =. µf) 6 C =. µf C =. µf 4 3 C =. µf 2 C = 2. k k 2 k PSRR, POWER SUPPLY REJECTION (db) Figure 7. Power Supply Rejection versus Frequency (C2 = ) 6 C =. µf C =. µf C =. µf 2. k k 2 k DEVICE DISSIPATION (mw) Figure. Device Dissipation,. Ω Load VCC = 2 V VCC = 6. V VCC = 3. V DEVICE DISSIPATION (mw) Figure 9. Device Dissipation, 6 Ω Load VCC = 6 V VCC = 2 V VCC = 6. V VCC = 3. V LOAD POWER (mw) LOAD POWER (mw) 6 MOTOROLA ANALOG IC DEVICE DATA

7 MC349 DEVICE DISSIPATION (mw) Figure. Device Dissipation, 32 Ω Load 2 VCC = 6 V VCC = 2 V 6 4 VCC = 6. V 2 VCC = 3. V LOAD POWER (mw) THD, TOTAL HARMONIC DISTORTION (%) VCC = 3. V, RL = 6 Ω Figure. Distortion versus Power (f =. khz, AVD = 34 db) VCC = 3. V, RL =. Ω VCC = 6 V, RL = 32 Ω V CC = 6. V, RL = 6 Ω VCC = 6. V, RL = 32 Ω VCC = 2 V, RL = 32 Ω POut, OUTPUT POWER (mw) THD, TOTAL HARMONIC DISTORTION (%) Figure 2. Distortion versus Power (f = 3. khz, AVD = 34 db) VCC = 3. V, RL = 6 Ω VCC = 3. V, RL =. Ω VCC = 6 V, RL = 32 Ω Limit VCC = 6. V, RL = 6 Ω VCC = 2 V, RL = 32 Ω POut, OUTPUT POWER (mw) VCC = 6. V, RL = 32 Ω THD, TOTAL HARMONIC DISTORTION (%) Figure 3. Distortion versus Power (f =, 3. khz, AVD = 2 db) VCC = 3. V, RL = 6 Ω. VCC = 3. V, RL =. Ω 6. VCC = 6. V, RL = 32 Ω VCC = 6 V, RL = 32 Ω Limit VCC = 6. V, RL = 6 Ω Limit VCC = 2 V, RL = 32 Ω POut, OUTPUT POWER (mw) LOAD POWER (mw) Figure 4. Maximum Allowable Load Power RL = 32 Ω 4 RL = 6 Ω 3 2 RL =. Ω TA = 2 CDerate at higher temperatures VCC, SUPPLY VOLTAGE (V) I CC, POWER SUPPLY CURRENT (ma) Figure. Power Supply Current RL = CD = CD = VCC VCC, SUPPLY VOLTAGE (V) MOTOROLA ANALOG IC DEVICE DATA 7

8 MC349 Figure 6. Small Signal Response Figure 7. Large Signal Response INPUT. mv/div INPUT mv/div OUTPUT 2 mv/div OUTPUT. V/DIV 2 µs/div 2 µs/div Figure. VO, VO2 versus Load Current..4 Figure 9. VO, VO2 versus Load Current V CC V OH (V) VCC 6 V, OUTPUT LOW LEVEL (V) TA = 2 C VCC = 2. V VCC = 3. V.9 TA = 2 C VOL.2 VCC 6. V ILOAD, LOAD CURRENT (ma) ILOAD, LOAD CURRENT (ma) 2 6 Figure 2. Input CD (Pin ) Figure 2. Audio Amplifier with High Input Impedance 7 k 6 VCC I CD, (µa) 2 4 Input. 3. k µf 2 # k 2 k 4. k 4. k #2 Speaker Valid for VCD VCC VCD, CHIP DISABLE VOLTAGE (V) k Differential Gain = 34 db Frequency Response: See Figure 3 Input Impedance 2 kω PSRR db MC349 7 Gnd Bias Circuit Disable MOTOROLA ANALOG IC DEVICE DATA

9 MC349 Figure 22. Audio Amplifier with Bass Suppression Figure 23. Frequency Response of Figure k Input. k µf 2 7 k # k 2 k k MC349 6 VCC 4. k 4. k #2 7 Gnd Bias Circuit Speaker Disable AVD, DIFFERENTIAL GAIN (db) k k 2 k Input Figure 24. Audio Amplifier with Bandpass Figure 2. Frequency Response of Figure k. k µf 2 pf # k 2 k k k k MC349 6 VCC 4. k 4. k #2 7 Gnd pf Bias Circuit Speaker Disable AVD, DIFFERENTIAL GAIN (db) k k 2 k Figure 26. Split Supply Operation Rf 7 k 6 VCC (. V to. V) Audio Input Ci. Ri 3. k Vin FC 4 3 # 4. k 4. k VO Speaker FC2 2 k 2 k k MC349 #2 Bias Circuit 7 VEE (. V to. V) VO2 CD k VCC 47 2 k 2 k Chip Disable NOTE: If V CC and V EE are not symmetrical about ground then FC must be connected through a capacitor to ground as shown on the front page. VEE MOTOROLA ANALOG IC DEVICE DATA 9

10 MC349 OUTLINE DIMENSIONS P SUFFIX PLASTIC PACKAGE CASE 626 ISSUE K NOTE 2 T SEATING PLANE H B 4 F A L C J N M D K G.3 (.) M T A M B M NOTES:. DIMENSION L TO CENTER OF LEAD WHEN FORMED PARALLEL. 2. PACKAGE CONTOUR OPTIONAL (ROUND OR SQUARE CORNERS). 3. DIMENSIONING AND TOLERANCING PER ANSI Y4.M, 92. MILLIMETERS INCHES DIM MIN MAX MIN MAX A B C D F G 2.4 BSC. BSC H J K L 7.62 BSC.3 BSC M N D SUFFIX PLASTIC PACKAGE CASE 7 (SO) ISSUE P T B K G A X D 4 4X P C.2 (.) M B M SEATING PLANE R.2 (.) M T B S A S X 4 J M F NOTES:. DIMENSIONS A AND B ARE DATUMS AND T IS A DATUM SURFACE. 2. DIMENSIONING AND TOLERANCING PER ANSI Y4.M, DIMENSIONS ARE IN MILLIMETER. 4. DIMENSION A AND B DO NOT INCLUDE MOLD PROTRUSION.. MAXIMUM MOLD PROTRUSION. PER SIDE. 6. DIMENSION D DOES NOT INCLUDE MOLD PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE.27 TOTAL IN EXCESS OF THE D DIMENSION AT MAXIMUM MATERIAL CONDITION. MILLIMETERS DIM MIN MAX A 4.. B C.3.7 D.3.49 F.4.2 G.27 BSC J..2 K..2 M 7 P. 6.2 R.2. MOTOROLA ANALOG IC DEVICE DATA

11 MC349 OUTLINE DIMENSIONS DTB SUFFIX PLASTIC PACKAGE CASE 94J (TSSOP) ISSUE O. (.6) T. (.6) T U L U. (.4) T SEATING PLANE S S PIN IDENT. D 2X L/2 C 4 G x A V K REF. (.4) M T U S V S B U H N N F DETAIL E J J SEE DETAIL E K K ÇÇÇ ÉÉ.2 (.) SECTION NN M W NOTES: DIMENSIONING AND TOLERANCING PER ANSI Y4.M, CONTROLLING DIMENSION: MILLIMETER. 3 DIMENSION A DOES NOT INCLUDE MOLD FLASH. PROTRUSIONS OR GATE BURRS. MOLD FLASH OR GATE BURRS SHALL NOT EXCEED. (.6) PER SIDE. 4 DIMENSION B DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSION. INTERLEAD FLASH OR PROTRUSION SHALL NOT EXCEED.2 (.) PER SIDE. DIMENSION K DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE. (.3) TOTAL IN EXCESS OF THE K DIMENSION AT MAXIMUM MATERIAL CONDITION. 6 TERMINAL NUMBERS ARE SHOWN FOR REFERENCE ONLY. 7 DIMENSION A AND B ARE TO BE DETERMINED AT DATUM PLANE W. MILLIMETERS INCHES DIM MIN MAX MIN MAX A B C.2.47 D F G.6 BSC.26 BSC H J J K K L 6.4 BSC.22 BSC M MOTOROLA ANALOG IC DEVICE DATA

12 MC349 Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Typical parameters which may be provided in Motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including Typicals must be validated for each customer application by customer s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer. How to reach us: USA / EUROPE / Locations Not Listed: Motorola Literature Distribution; JAPAN: Nippon Motorola Ltd.; TatsumiSPDJLDC, 6F SeibuButsuryuCenter, P.O. Box 292; Phoenix, Arizona or Tatsumi KotoKu, Tokyo 3, Japan ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; B Tai Ping Industrial Park, Ting Kok Road, Tai Po, N.T., Hong Kong MOTOROLA ANALOG IC DEVICE MC349/D DATA

SEMICONDUCTOR TECHNICAL DATA KIA6419P/F DIP-8 FLP-8 LOW POWER AUDIO AMPLIFIER

SEMICONDUCTOR TECHNICAL DATA KIA9P/F BIPOLAR LINEAR INTEGRATED CIRCUIT LOW POWER AUDIO AMPLIFIER The KIA9P/F is a low power audio amplifier integrated circuit intended (Primarily) for telephone applications,