PA4894G-SM2-R

PA4894 UTC | Alldatasheet

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UNISONIC TECHNOLOGIES CO., LTD PA4894 CMOS IC w w w . u n i s o n i c . c o m . t w 1 of 11 Copyright © 2009 Unisonic Technologies Co., Ltd QW-R502-379.A

1.8 WATT DIFFERENTIAL

„ DESCRIPTION The UTC PA4894 is a differential audio power amplifier, characterized by its selectable shutdown mode for flexible operation. Shutdown may be enabled by either logic high or low depending on the voltage applied on the SD MODE pin and the shutdown mode features low power consumption. This device provides custom ers perfect sound performance by its high quality audio, moreover, less external components and lower power dissipation are required. Operating with a 5.5V power supply, the UTC PA4894 is capable of driving an 8.0 Ω load at a continuous average output of 1.8W under a 10% THD+N. If it works with a 5.0V voltage under the same load conditions, 1.0W power will be delivered and the distortion will be less than 0.01%. The UTC PA4894 incorporates protection circuit to avoid the click and pop noise, which may occur during the transition state between turn-on and turn-off. The UTC PA4894 can be directly connected to a battery without an LDO since it has perfect PSRR. The UTC PA4894 can be configured externally with resistor s to provide a controlled gain and with bypass capacitor to provide a controlled turn-on time for more flexibility. The UTC PA4894 is suitable for applications, such as portable electronic devices, PDAs and mobile phones. MSOP-10 „ FEATURES * Differential amplification * Selectable and low current shutdown mode * 1.0W/Ch(typ.)into a 8Ω load @5.0V * Directly connected to the battery due to excellent PSRR * Operation supply: 2.2 V-5.5 V * External controlled gain and turn-on time configuration * Circuits for protection * Thermal overload protection circuit * “Click and pop” noise protection circuit * Halogen Free „ ORDERING INFORMATION Ordering Number Package Packing PA4894G-SM2-R MSOP-10 Tape Reel

UNISONIC TECHNOLOGIES CO., LTD 2 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ PIN CONFIGURATION „ PIN DESCRIPTION PIN NO. PIN NAME TYPE DESCRIPTION

1 SD SELECT O (Note)

2 INM I Negative differential input

3 SD MODE I Shutdown high or low selectivity (Note)

4 INP I Positive differential input

5 BYPASS O Bypass capacitor pin which provides the common mode voltage

6 OUTB I Negative BTL output

7 V M I Ground

8 NC - No connection

9 V P I Positive analog supply of the cell

10 OUTA I Positive BTL output

Note: The SD SELECT pin must be toggled to the same state as the SD MODE pin to force the device in shutdown mode.

UNISONIC TECHNOLOGIES CO., LTD 3 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ BLOCK DIAGRAM SHUTDOWN CONTROL VP 2INM BYPASS SD SELECT SD MODE INP VM OUTB OUTA

UNISONIC TECHNOLOGIES CO., LTD 4 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ ABSOLUTE MAXIMUM RATING (Ta=25°C, unless otherwise specified) PARAMETER SYMBOL RATINGS UNIT Supply Voltage V P 6.0 V Operating Supply Voltage V OPR 2.2 ~ 5.5 V Input Voltage V IN -0.3 ~ V CC +0.3 V Max Output Current I OUT 500 mA Power Dissipation (Note 2) P D Internally Limited Junction Temperature T J 150 °C Operating Temperature (TA) T OPR -40 ~+85 °C Storage Temperature Range T STG −65 ~ +150 °C Notes: 1. Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. 2. The thermal shutdown set to 160°C (typical) av oids irreversible damage on the device due to power dissipation. „ THERMAL DATA PARAMETER SYMBOL RATINGS UNIT Junction to Ambient θJA 200 °C/W „ ELECTRICAL CHARACTERISTICS (Ta= −40°C~ +85°C, unless otherwise specified). PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT Common Mode Voltage V CM VP/2 V High V THD(H) 1.4 V SD Select Threshold Low V THD(L) 0.4 V VP = 3.0V, RL= 8.0Ω 2.5 V Ta= 25°C 4.0 4.3 V Output Swing V O(SW) VP = 5.0V, RL= 8.0Ω Ta= -40°C ~ +85°C 3.85 V Output Offset Voltage V O(OFF) 2.2V ≤VP≤5.5V -30 1.0 30 mV VP = 3.0 V, No Load 1.9 mA VP = 5.0 V, No Load 2.1 mA VP = 3.0 V, 8.0Ω 2.0 mASupply Quiescent Current I Q VP = 5.0 V, 8.0 Ω 2.2 4.0 mA Ta= 25°C 20 600 nAShutdown Current I SHDN 2.2V≤VP≤5.5V SDM=SDS=GND Ta= -40°C ~ +85°C 2.0 μA Turning On Time T WU C BYP = 1.0μF 140 ms Turning Off Time T SD 20 ms VP = 3.0 V 0.39 W VP = 3.3 V 0.48 W RMS Output Power P O(RMS) R L= 8.0Ω, THD+N<0.1% VP = 5.0 V 1.08 W VP=5.0V -80 dBF=217 Hz VP=3.0V -80 dB VP=5.0V -85 dBPower Supply Ratio PSRR G=2.0, RL=8.0Ω CBYP= 1.0μF VP(RIPP_PP)= 200mV Input Terminated with 10Ω F=1.0 kHz VP=3.0V -85 dB Over Temperature Shutdown OTS 160 °C VP = 3.0 V, PO(RMS)= 380mW 64 % Efficiency η VP = 5.0 V, PO(RMS)= 1.0W 63 % VP = 3.0V, F = 1.0 kHz Total Harmonic Distortion THD VP = 5.0V, F = 1.0 kHz Notes: 1. Min and Max limits are guaranteed by design, test or statistical analysis. 2. See page 8 for a theoretical approach of these parameters.

UNISONIC TECHNOLOGIES CO., LTD 5 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ TYPICAL APPLICATION CIRCUIT Differential Input RL CS 1µF VP 20kΩ RF1 Cb 1µF CI1 RIN1 20kΩ390nF CI2 RIN2 20kΩ390nF SHUTDOWN CONTROL SD MODE SD SELECT STATUS SHUTDOWN ON ON SHUTDOWN 20kΩ RF2 VM INP INM VP OUTB Negative Diff Input from DAC Positive Diff Input from DAC OUTA SHUTDOWN CONTROL BYPASS SD SELECT SD MODE Driving Headphone

UNISONIC TECHNOLOGIES CO., LTD 6 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ APPLICATION INFORMATION Detailed Description The UTC PA4894 includes two power amplifiers internally. Two of them provide a controlled gain with external components RIN and RF; the gain is calculated by the ratios of the re sistors. The load is driven differentially through OUTA and OUTB outputs. This configuration is saving the use of an output coupling capacitor. The UTC PA4894 is operating on a 2.6V to 5.5V power supply, when V P is 2.6V it delivers 320mW rms output Internal Power Amplifier The internal power amplifier contains output PMOS and NM OS transistors, which is used to deliver the output power of the specifications without clipping. The channel resistance (R ON) of the NMOS and PMOS transistors does not exceed 0.6Ω when they drive current. The structure of the internal power amplifier is composed of three sy mmetrical gain stages, first and medium gain stages are transconductance gain stages to obtain maximum bandwidth and DC gain. Turn-On and Turn-Off Transitions Output power in the load established must be slowly or cut for minimize the click and pop noise during the transitions between turn-on and turn-off conditions. When shutdown mode is over，, the bypass voltage begins to rise exponentially and once the output DC level is around the common mode voltage, the turn-on mode is over. The turn−on time is determined by the following equation (at 25°C): TON = 0.95×R×CBYP (CBYP: bypass capacitor R: internal 150 k resistor with a 25% accuracy) The turned off operation is as the same as the turn-on operation. Through applying a same logic state on the SD SELECT and SD MODE pins, the system enters this m ode. During the shutdown m ode, amplifier outputs are connected to the ground to discharge. Shutdown Function When SD SELECT and SD MODE pins are in the same l ogic state, the system ent ers shutdown mode. This brings flexibility to the design, as the SD MODE pin must be permanently co nnected to VP or GND on the PCB. In many applications, the output of a microcontroller or microprocessor is connected to the SD SELECT pin, so it is not better to allow this pin float. During the shutdown state, the DC quiescent current has a typical value of 10nA. Current Limit Circuit The current limit circuit protects the device from damage from excessive current. The maximum output power of the circuit (P O(RMS) =1.0W, V P = 5.0V, R L = 8.0 Ω) requires a peak current in the load of 500mA. When short-circuit occurs between both outputs, the current limit in the l oad is fixed to 800mA for limiting the excessive power consumption.

UNISONIC TECHNOLOGIES CO., LTD 7 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ APPLICATION INFORMATION(Cont.) Thermal Overload Protection When the temperature of the UTC PA4894 is higher than160°C for any reasons, the thermal overload protection function turns the amplifiers off until the temperature drop below 140°C. The UTC PA4894 is unity gain stable and requires no external components besides gain setting resistors, an input coupling capacitor and a proper bypa ssing capacitor in the typical applicati on. Both internal amplifiers are externally configurable (RF and RIN) with gain configuration. The differential ended amplifier has two main benefits compared to single-ended: * The differential ended amplifier will yield 4 times lar ger the output power on the load at the same conditions compared to a single ended amplifier. * Output pins (OUTA and OUTB) are bias ed at the same potentia l VP/2, which is saving the use of an output coupling capacitor that is required with a single ended amplifier configuration. The differential closed loop gain of the amplifier is correlated as seen in the following ratio: )RMS(IN )RMS(O IN F V V=R R=Avd VO(RMS): the rms value of the voltage seen by the load VIN(RMS):the rms value of the input differential signal) Output power delivered to the load is defined as follows: L 2)PEAK(O )RMS(O R×2 )V(=P VO(PEAK) is the peak differential output voltage When choosing gain configuration to obt ain the desired output power, check t hat the amplifier is not current limited or clipped. The maximum current which can be delivered to the load is 500mA L )PEAK(O )PEAK(O R V=I Gain−Setting Resistor Selection (RIN and RF) The UTC PA4894 requires low gain configurations for a better performance. Since the RIN and RF determine the closed−loop gain of both amplifiers, it is critical to choose both of them. The low gain configuration minimizes THD + noise val ues and maximizes the signal to noise ratio, and the amplifier can still be used without running into the bandwidth limitations. A closed loop gain in the range from 2 ~ 5 is recommended to optimize overall system performance. 22 kΩ input resistor (RIN)is recommended. Input Capacitor Selection (CIN) The input coupling capacitor blocks the DC voltage at the amplifier input terminal. A high−pass filter is generated by this capacitor and Rin, and the cut−off frequency is defined by the following fomula: ININ C C×R×π×2 1=f The size of the capacitor must be large enough to coup le in low frequencies without severe attenuation. However a large input coupling capacitor requires more ti me to reach its quiescent DC voltage (VP/2) and can increase the turn−on pops. An input capacitor value between 0.1μ and 0.39μF is sugguested in most applications. Bypass Capacitor Selection (CBYP) To avoid the pop noise, the bapass capacitor should be ch osen prompty. The bypass capacitor determines the rate at which this device starts and it provides half−supply filtering. A 1.0μF bypass capacitor value (CIN≤ 0.39μF) should produce clickless and popless shutdown transitions. So a 1.0μF bypassing capacitor is recommended to be used.

UNISONIC TECHNOLOGIES CO., LTD 8 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ APPLICATION INFORMATION(Cont.) Demo Board Schematic SHUTDOWN CONTROL VM INP BYPASS INM VP OUTB OUTA 1µF VP 20kΩ 20kΩ RL 20kΩ1µF R2C2 20kΩ1µF R1C1 VP GND VP 100kΩ 1µF SD SELECT SD MODE

UNISONIC TECHNOLOGIES CO., LTD 9 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ TYPICAL CHARACTERISTICS 0 200 400 600 800 1000 1200 0.001 0.01 0.1 Output Power (mW) THD+N (%) THD+N vs. Output Power VP=5V RL=8Ω F=1kHz 0 100 300 400 500 0.001 0.01 0.1 Output Power (mW) THD+N (%) THD+N vs. Output Power VP=3V RL=8Ω F=1kHz 200 THD+N (%) THD+N (%) 2.5 3.0 4.0 200 Output Power (mW) THD+N vs. Output Power 3.5 RL=8Ω F=1kHz THD+N =1% THD+N =10% 4.5 5.0 5.5 400 600 800 1000 1200 1400 1800 2000 1600

UNISONIC TECHNOLOGIES CO., LTD 10 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ TYPICAL CHARACTERISTICS(Cont.) Power Dissipation, PD (W) Power Dissipation, PD (W) VP=3V RL=8Ω F=1KHz THD+N<0.1% 00 . 1 0 . 2 0 . 3 0 . 4 0.05 Output Power, POUT (W) Power DissipationOutput Power 0.1 0.15 0.2 0.25 00 . 0 5 0.05 Output Power, POUT (W) Power DissipationOutput Power 0.1 0.15 0.2

0.35 RL=4Ω

RL=8Ω VP=2.6V F=1KHz THD+N<0.1% 0.25 0.3 0.4 Turning-on Sequence Turning-on Sequence Zoom

UNISONIC TECHNOLOGIES CO., LTD 11 of 11 www.unisonic.com.tw Q W - R 5 0 2 - 3 7 9 . A „ TYPICAL CHARACTERISTICS(Cont.) UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice.