PA4101 PUNK with µP Supervisor 95000 ANALOG PRODUCTS DIVISION Features General Description • • • • • • • • The PA4101 is a low power monolithic CMOS mixed signal device. Its function is to control power supply transition noise in audio circuits and systems. It requires very few external components for its operation and works from low to medium power supply voltages of 2.7V to 5.5V. As the power supply ramps ON or OFF, the PA4101 ensures that audio inputs to succeeding amplifiers are switched to a convenient low impedance voltage rail. This causes the amplifiers to remain silent as the power supply changes state (from ON to OFF and vice versa). Precision supply voltage monitoring Reset Timeout Delay 36dB mute attenuation 2.7V to 5.5V single-supply operation ESD protected outputs Low supply current Soft Mute out for driving additional channels SOIC 14 Applications • • • • • • • Also included in the device is a digital control pin which can be used by a control device such as a micro controller or a microprocessor or any other digital controller to enable the audio mute function. This supervisory circuit provides maximum flexibility for monitoring power supplies and battery controlled functions in systems without backup batteries. Set-top boxes Cell phones PDA’s Portable DVD players Portable MP3 players Notebook Audio Critical µP Power Monitoring A Reset is asserted during power up, power down and brownout conditions. RESET is guaranteed down to Vcc of 1.0V. Pin Layout RESET 1 14 CEXT RESET 2 13 CHIPOP VCC 3 12 SMUTEOUT MCUVCC 4 11 NC RCS 5 10 MUTE2 6 9 MUTE1 7 8 GND MUTECONT NC Low line output. The early warning indicator goes low when the supply voltage drops to a value 2% higher than the reset threshold voltage The PA4101 consumes less than 50μA of supply current while providing more than 36dB of mute attenuation at the audio lines. ESD (Human Body Model) protection circuitry on the outputs protects the PA4101 and devices further up the signal chain. The PA4101 is available as a 14L SOIC package and is specified for operation over the -40°C to +85°C temperature range. Functional Diagram Typical Application RST µP Mute Control Chip OP µP VCC RSET Right Input 2 4 Vcc R2 220Ω Right Output 1 13 C4 47µF R3 10KΩ 6 R1 500KΩ PA4101 10 Mute2 9 Mute1 RCS 5 C3 0.5µF CEXT 14 8 3 12 Left Input R4 220Ω Left Output C2 10µF C1 0.1µF C5 47µF SMUTEOUT R5 10KΩ Vcc 561 E. Elliot Road #175 Chandler, AZ 85225 Tel: (480) 539-2900. Fax: (602) 431-2288 www.protekanalog.com 95000 Rev. 0. 01/08 NOT FOR USE IN LIFE SUPPORT SYSTEMS 69 PA4101 PUNK with µP Supervisor ANALOG PRODUCTS DIVISION Absolute Maximum Ratings Sustained operation at or above the following ratings is not recommended. Catastrophic and irreversible damage will occur to the device at or above these ratings. Symbol Description Rating VX Voltage at any pin -0.3 to 7.0+0.3 V IX Current at any pin 500mA TA Ambient Temperature 150 ° C TS Storage Temperature 200 ° C TSOL Soldering Temperature 270 ° C Recommended Operating Conditions: Unless otherwise specified, VDD=2.7±10%, TA = Ambient Temperature = 25 deg C. DC Operating Conditions Symbol Parameter Condition Unit Limit Min Typ VDD Positive Power Supply Operating IDD VDD Current Operating TA Ambient Temperature Operating VOH Logic High O/P Voltage IOH=100μA VOL Logic Low O/P Voltage IOL=-100μA VIH Logic High I/P Voltage IIH=1μA VIL Logic Low I/P Voltage IIL=1μA 0.3 V RON FET ON Resistance VDD=2.7V, VDFET=0.4V 1.5 Ω Supervisor Operating Conditions Symbol Parameter 2.7 Max -30 Operating VRSTH Reset Threshold VDD falling -40 to 85 degC VHYS Reset Threshold hysteresis VHYS 1 mA 85 °C V 0.2 VDD-0.3 V V Unit Limit Min Reset Voltage V VDD-0.1 Condition VRST 5.5 Typ Max 2.5 V -2.5 2.5 % VDD=2.7V 17 29 mV Reset Threshold hysteresis VDD=5.5V 36 60 mV TRD VDD – Reset Delay VDD falling at 1mv/μs 20 μs TRP Reset Time Out Period 75 ms 44 561 E. Elliot Road #175 Chandler, AZ 85225 Tel: (480) 539-2900. Fax: (602) 431-2288 www.protekanalog.com 95000 Rev. 0. 01/08 NOT FOR USE IN LIFE SUPPORT SYSTEMS 70 PA4101 PUNK with µP Supervisor ANALOG PRODUCTS DIVISION Mute Operating Conditions Symbol Parameter Limit Condition Min Typ Unit Max MOFFD Mute release delay Mute Control=VIL Set by ext. capacitor CM 10 300 mS MSTD Soft mute fall/rise time Mute Control transitions to VIH. Set by ext. capacitor CEXT 1 300 mS MPDEL Mute ON Delay Power drops by 10% 5 μS NFETV NFET open drain volt 12 V Pin Out Pin Name Function RESET RESET Inverted Reset output from the voltage supervisor 3 VCC Positive power supply. 2.7V to 5.5V ±10% 4 MCUVCC Microprocessor power supply 5 RCS Power On mute delay resistor-capacitor connection. 6 MUTECONT Mute control signal from microprocessor. 8 GND Ground. 9 MUTE1 Open Drain output of NFET 1 10 MUTE2 Open Drain output of NFET 2 1 2 Reset output from the voltage supervisory circuit. 12 SMUTEOUT Soft Mute OUT for multiple channels. 13 CHIPOP Supply voltage selector. Connect to GND for 2.7V, VCC for 5.5V. 14 CEXT Soft mute delay capacitor. Operation Of Supervisor Circuit. The reset input of a µP initializes the device into a known state. The PA4101 supervisor circuitry asserts a forced reset output to prevent code execution errors during Power-up, power-down and brownout conditions. Supervisor Application VIN VOUT C RESET is valid for VCC >1Volt. Once VCC exceeds the threshold, an internal timer maintains the output for the reset period timeout. After this interval, reset goes high. Any time VCC drops below the reset threshold, the reset activates. When VCC again rises above the threshold, the internal timer starts. Reset holds until VCC exceeds the reset threshold for longer than the reset timeout period. After this time the reset release VCC RESET R GND VIN VRSTH VOUT RESET tRP 561 E. Elliot Road #175 Chandler, AZ 85225 Tel: (480) 539-2900. Fax: (602) 431-2288 www.protekanalog.com 95000 Rev. 0. 01/08 NOT FOR USE IN LIFE SUPPORT SYSTEMS 71 ANALOG PRODUCTS DIVISION PA4101 PUNK with µP Supervisor Timing Diagram Supervisor VRSTH VRST VCC tRD tRP tRP RESET THEORY OF OPERATION Audio Muting STARTUP During Startup, the Power supply ramps from 0V to VCC. This time is usually in excess of 20ms. As soon as this change in voltage is sensed, PUNK latches the Mute Controller outputs to HIGH, thus “muting” the lines. This is the Startup Operation (figure 1). The duration for which the controller outputs are latched HIGH can be controlled by an external RC circuit. When the voltage at this RC pin reaches a certain threshold, the mute controller releases the lines (Gate voltage is LOW) and Normal Operation starts. Figure 1: Startup Pop-Noise Reduction SHUTDOWN During Shutdown, the reverse process happens. As the power supply reaches the threshold on its way down, the mute controller again latches the outputs to HIGH, thus “muting” the lines (figure 2). This muting prevents unwanted signal spikes from getting to the power amplifiers. However, for optimal performance, it is suggested to mute the lines using the MUTECONT signal before power down. This process will ensure that the pop noise involved during shutdown is diminished SOFTMUTE During normal operation, PUNK is in OFF state. But if there arises a situation when the audio lines need to be muted, the designer can do this by asserting the MUTECONT signal to HIGH. This will initiate a SOFTMUTE sequence (figure 3). When the MUTECONT signal is asserted, the mute controller gradually ramps the control voltages in a “SOFT” fashion so as to provide a soft mute operation. The mute delay is fully controllable by the designer by using an external capacitor at CEXT. Typical values of CEXT are between 0.1μF and 0.5μF. The reverse happens when the MUTECONT signal is released. This operation is explained in detail in the Application Circuit section. Figure 2: Shutdown Pop-Noise Reduction Figure 3: SOFT mute operation 561 E. Elliot Road #175 Chandler, AZ 85225 Tel: (480) 539-2900. Fax: (602) 431-2288 www.protekanalog.com 95000 Rev. 0. 01/08 NOT FOR USE IN LIFE SUPPORT SYSTEMS 72 PA4101 PUNK with µP Supervisor ANALOG PRODUCTS DIVISION Typical Application Audio Muting. VCC 3.3V R15 10K LINE OUT LEFT C13 10µF V.S. 1 C14 10µF FUNCTION. GENERATOR 1V PTP 1KHz SINE WAVE R17 100Ω LINE OUT RIGHT R16 10K R19 100Ω C15 10µF 12 3 10 MUTE 2 R18 10K R20 10K SMUTEOUT 9 MUTE 1 VCC D1 C16 10µF R14 22K R13 240K C12 1µF 5 MUTECONT RCS CEXT 14 6 GND 8 R21 10K U2 74LS04 S1 Notes: 1. 2. 3. 4. 5. 6. 7. 8. A Set Top Box audio output is “simulated” using C14, R15, R16 and VS 1. VS 1 is a signal generator having an output impedance of 50Ohm. U2 is the IC 74LS04. U2 runs off of PUNK Vcc (Output of D1, C16 and R14). Input to U2 is the Set Top Box Vcc Switch S1 serves as a manual “Audio Mute” to enable the muting function. Scope probes were attached to Set Top Box Power Supply and Line Out. Waveform shown in Figure 4 to Figure 9 561 E. Elliot Road #175 Chandler, AZ 85225 Tel: (480) 539-2900. Fax: (602) 431-2288 www.protekanalog.com 95000 Rev. 0. 01/08 NOT FOR USE IN LIFE SUPPORT SYSTEMS 73 ANALOG PRODUCTS DIVISION PA4101 PUNK with µP Supervisor Figure 4: Startup Pop-Noise without PUNK Figure 7: Shutdown Pop-Noise with PUNK Figure 5: Shutdown Pop-Noise without PUNK Figure8: Audio Mute Enable Figure 6: Startup Pop-Noise with PUNK Figure 9: Audio Mute Disable 561 E. Elliot Road #175 Chandler, AZ 85225 Tel: (480) 539-2900. Fax: (602) 431-2288 www.protekanalog.com 95000 Rev. 0. 01/08 NOT FOR USE IN LIFE SUPPORT SYSTEMS 74 PA4101 PUNK with µP Supervisor ANALOG PRODUCTS DIVISION Package Layout and Dimensions Dim P1 P2 P3 P4 L1 L2 L3 p g P1 P4 P2 MIN 0.337 0.230 0.060 0.150 0.014 0.007 0.023 0.050 0.004 Inches TYP 0.341 0.238 0.065 0.155 0.016 0.009 0.026 0.050 0.006 MIN 0.346 0.244 0.070 0.157 0.019 0.010 0.029 0.050 0.008 L3 TOP VIEW L2 END VIEW P3 0.050” TYP p 0.030” ± 0.005” g L1 SIDE VIEW 0.160” ± 0.005” 0.245” MIN 0.045” ± 0.005” Recommended Pattern Layout Life Support Policy PROTEK ANALOG'S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF PROTEK DEVICES 561 E. Elliot Road #175 Chandler, AZ 85225 Tel: (480) 539-2900. Fax: (602) 431-2288 www.protekanalog.com 95000 Rev. 0. 01/08 NOT FOR USE IN LIFE SUPPORT SYSTEMS 75