PROTEC PA4101

PA4101
PUNK with µP Supervisor
95000
ANALOG PRODUCTS DIVISION
Features
General Description
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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
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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