Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A DESCRIPTION PT2253A is an electronic volume controller IC utilizing CMOS Technology specially designed for use on audio equipments. It has two (2) built-in channels making it ideally suitable for mono and stereo sound applications. PT2253A provides a wide frequency response range and a very low harmonic distortion to mention a few; thereby guaranteeing a highly effective and reliable performance. FEATURES • CMOS technology • Low power consumption • Operating voltage range: Vcc=6 ~ 12V (Backup voltage is up to 4V) • 0dB to -68dB attenuation controlled by 2dB/step • 2 channels in each chip • Capable to control attenuation by a built-in oscillator and Up/Down pin • Single power supply or dual power supplies of (+) and (-) can be used • Wide frequency response range • Very low harmonic distortion • Available in 16 pin, DIP package APPLICATIONS • Audio Equipment Volume Control • Traditional VR Replacement PT2253A V2.8 -1- December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A BLOCK DIAGRAM Vcc U/D U/D CK OSC 7 BITS BIDIRECTIONAL SHIFT REGISTER Vss /INH 5 BITS BIDIRECTIONAL CK SHIFT REGISTER U/D INT AUTO INITIALIZE CIRCUIT INT OSC CONSTANT CURRENT CIRCUIT DCO Vcc L-OUT1 R-OUT1 A-SW A-SW A-SW A-SW A-SW A-SW CK 7 BITS LATCH CIRCUIT A-SW 7 BITS LATCH CIRCUIT CK L-IN1 CK CK A-SW A-SW A-SW A-SW A-SW A-SW A-SW A-GND A-SW A-SW A-SW A-SW A-SW L-OUT2 PT2253A V2.8 CK 6 BITS LATCH CIRCUIT A-SW CK 6 BITS LATCH CIRCUIT A-GND L-IN2 R-IN1 CK CK -2- A-SW R-IN2 A-SW A-SW A-SW A-SW A-SW R-OUT2 December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A PIN CONFIGURATION Vss 1 16 Vcc L-OUT1 L-IN1 2 3 15 14 R-OUT1 R-IN1 A-GND 4 13 A-GND L-IN2 5 12 R-IN2 LOUT2 /INH 6 11 7 10 R-OUT2 U/D DCO 8 9 OSC PT2253A PIN DESCRIPTION Pin Name I/O Description Pin No. Vss Power Negative Power Supply 1 10dB/Step Attenuator Output L-OUT1 O 2 A signal applied to ‘IN’ is attenuated into 7 steps from 0dB to -60dB. L-IN1 I 10dB/Step Attenuator Input 3 A-GND GND Analog Ground Pin 4 L-IN2 I 2dB/Step Attenuator Input 5 2dB/Step Attenuator Output L-OUT2 O 6 A signal applied to “IN” is attenuated into 5 steps from 0dB to -8dB. Inhibit Terminal. /INH I At “L” level, all inputs and outputs are disabled. 7 At “H” level, operation is normal. DCO O DC Current Output Pin 8 OSC I/O RC Connecting Pin for the Oscillator 9 U/D I Attenuator Up/Down Control Pin 10 R-OUT2 O 2dB/Step Attenuator Output, same as L-OUT2. 11 R-IN2 I 2dB/Step Attenuator Input, same as L-IN2. 12 A-GND GND Analog Ground Pin 13 R-IN1 I 10dB/Step Attenuator Input, same as L-IN1. 14 R-OUT1 O 10dB/Step Attenuator Output, same as L-OUT1. 15 Vcc Power Positive Power Supply 16 PT2253A V2.8 -3- December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A FUNCTION DESCRIPTION ATTENUATION SETTING The Attenuation can be increased or decreased depending on the state of the U/D Pin (either “H” or “L” Level) by actuating the built-in oscillator. When power is applied, the attenuation is automatically set at -40dB. POWER SUPPLY U/D OSC -30dB -32dB -34dB -36dB -38dB -40dB When the DOWN Key is pressed, the U/D Pin goes to the “L” Level and the oscillator is actuated in the down state. Thus, attenuation is increased. Conversely, when the UP Key is pressed, the U/D Pin goes to the “H” Level and the oscillator is actuated in the up state. Thus, attenuation is decreased. Oscillation frequency (fosc) is dependent on the Cx and the Rx and is determined by the following equation: fosc = 1 Hz 0.7 (Cx)(Rx) where: Rs ≥ 3Rx PT2253A V2.8 -4- December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A Vcc Rs Cx OSC Vcc Rx UP OSC U/D + DOWN 1µF Rx=33KΩ Cx=4.7µF Rs=100KΩ Vss PT2253A V2.8 -5- December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A ATTENUATION DISPLAY OUTPUT PT2253A has a DC Current Output Pin (DCO). The output level is divided into 13 steps. Please refer to the table below: Step DCO Attenuation 0 0 -64dB ~ ∞ 1 2 3 4 5 6 7 8 9 10 11 12 13 I 2I 3I 4I 5I 6I 7I 8I 9I 10I 11I 12I 13I -60dB ~ -62dB -54dB ~ -58dB -50dB ~ -52dB -44dB ~ -48dB -40dB ~ -42dB -34dB ~ -38dB -30dB ~ -32dB -24dB ~ -28dB -20dB ~ -22dB -14dB ~ -18dB -10dB ~ -12dB -4dB ~ - 8dB 0dB ~ -2dB Current value may fluctuate depending on the IC. When high precision is required, use a variable resistor as a load resistor. 13 12 11 10 8 9 1K 8 7 About 1.3 V 6 Vss 5 4 3 2 STEP 0 PT2253A V2.8 1 About 100mV + 30mV -6- Vss December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A ATTENUATOR Attenuator 1 attenuates 0 ~ -60dB at 10dB/step. Attenuator 2 attenuates 0 ~ -8dB at 2dB/step. BUFFER AMP 0dB 0 OUT1 IN1 IN2 OUT2 -10 -2 -20 -4 RATT-2 -30 -6 RATT-1 -40 -8 -50 ∞ ATTENUATOR 2 -60 ATTENUATOR 1 A-GND RATT-2=20K Ω (TYP.) RATT-1=50KΩ(TYP.) If there is the possibility of excessive voltage in the attenuator, it is recommended that a protective diode be inserted. Please refer to the diagram below. Vcc Vcc IN Vss Vss PT2253A V2.8 -7- December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A POWER SUPPLY DUAL POWER SUPPLY +Vcc Vcc U/D OSC 0V A-GND Vss /INH OSC U/D -Vss DCO DC UP Vcc DOWN SINGLE POWER SUPPLY + +Vcc Vcc U/D OSC /INH DCO 1/2 VDD (A-GND) A-GND Vss 0V (Vss) DC Vcc PT2253A V2.8 -8- December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A INITIALIZATION WHEN POWER ON PT2253A has the built-in auto-initializing function for during the Power ON period. It has the power supply on reset for the initialization of the chip. If the power supply rises too fast, the initialization may not be fully effected. For initialization to be fully effective, it is necessary to satisfy the following conditions: 1. The /INH Terminal must be raised simultaneously with the supply voltage. 2. Initial attenuation level is -40dB Please refer to the following diagram. Vcc-Vss = 4.0 V Vcc-Vss or /INH TERMINAL VOLTAGE T > 1 msec T Note: If Vcc-Vss drops below 4.0V, the auto-initializing function is actuated. BACK UP WHEN POWER OFF When /INH Pin is set at “L” Level, all input and output pins are disabled and the current consumption is reduced to the minimum. Under this condition, the backup by means of a capacitor becomes possible. An example of this application when a backup capacitor is used is shown below. Vcc VDD 10K Vcc 10K 1000µ 16V + - PT2253A Vss /INH -Vss 51K If Vcc-Vss drops below 4V, the backup becomes impossible. PT2253A V2.8 -9- December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A ABSOLUTE MAXIMUM RATINGS Parameter Symbol Ratings Operating temperature Topr -45 ~ +85 Unit ℃ Storage temperature Tstg -65 ~ +150 ℃ DC ELECTRICAL CHARACTERISTICS (Unless otherwise specified, Vcc=12V, Vss=0V and Ta=25℃) Parameter Symbol Conditions Min. Operating supply voltage Vcc 6 Operating supply current Icc Vcc=12V Stand-by-current ISB /INH=0V OSC=12V Input voltage “H” Level VIH 0.8 x Vcc (/INH, U/D) “L” Level VIL Vss - 0.3 Attenuator 1 Attenuation level RATT-1 25 (10dB/step) resistor is set to 0dB Attenuator 2 Attenuation level RATT-2 10 (2dB/step) resistor is set to 0dB Bias Vcc/2=6V Max. input amplitude Vin Fin=1KHz ATT=0dB Operating oscillation fosc 5 frequency DCO output current IDCO 1 step 70 PT2253A V2.8 - 10 - Typ. 1 Max. 12 3 Unit V mA - 10 µA - Vcc + 0.3 0.2 x Vcc V 50 70 KΩ 20 28 KΩ - 4.0 Vrms - 10 KHz 100 140 µA December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A ELECTRICAL CHARACTERISTICS (Unless otherwise specified, Vcc=6V, Vss=-6V, GND=0V) IN1 ~ OUT 1 Parameter Symbol Signal to noise ratio S/N Frequency response Fr Noise floor NF Total harmonic distortion THD Condition ATT=0dB Fin=1KHz Vin=1.0Vrms ATT=-10dB Fin=1KHz Vin=1.0Vp-p Vin=0V, ATT=0dB ATT=-10dB Fin=1KHz Vin=1.0Vrms Max. Unit 97 dB 657 KHz 0.015 mV 0.010 % IN2 ~ OUT2 Parameter Symbol Signal to noise ratio S/N Frequency response Fr Noise floor NF Total harmonic distortion PT2253A V2.8 THD - 11 - Condition ATT = 0dB Fin=1KHz Vin=1.0Vrms ATT=-2dB Fin=1KHz Vin=1.0Vp-p Vin=0V ATT=0dB ATT=-2dB Fin=1KHz Vin=1.0Vrms Max. Unit 95 dB 1820 KHz 0.022 mV 0.009 % December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A APPLICATION CIRCUIT 1 DUAL POWER SUPPLY (L-CHANNEL ONLY) Vss -6V 3 10 µF + + 4 LM358 _ 2 1 8 VDD +6V 10 µF + Vcc Vss 10 µF L-OUT1 R-OUT1 + R-IN1 L-IN1 INPUT GROUND A-GND 10 µF + A-GND L-IN2 OUTPUT R-IN2 L-OUT2 R-OUT2 /INH U/D DCO OSC PT2253A + CX 4.7µ + 10K RS 100K fosc = 1 µF RX 33K 1 (0.7) (CX)( RX) RS ≥ 3RX 1N4148 UP SW PT2253A V2.8 1N4148 - 12 - DOWN SW December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A APPLICATION CIRCUIT 2 DUAL POWER SUPPLY (L-CHANNEL ONLY) Vss -6V 3 10µF 4 + LM358 _ + 2 1 8 68pF VDD +6V 10µF 0.15 F + 51K 110K Vss L-OUT1 R-OUT1 10µF + L-IN1 A-GND GROUND OUTPUT L-IN2 + 10µF R-IN1 A-GND R-IN2 L-OUT2 R-OUT2 /INH U/D DCO OSC + INPUT Vcc CX 4.7µ PT2253A 10K 1N4148 + RS 100K fosc = 1 1µF RX 33K (0.7)(CX)( RX) RS ≥ 3RX 1N4148 UP SW DOWN SW Note: Since the buffer amp between Att-1 and Att-2 is already 10dB voltage gain, higher input level may cause OP amp’s output clipping. To avoid unwanted distortion, the input signal level applied at IN-1 should not be over 1Vrms. PT2253A V2.8 - 13 - December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A APPLICATION CIRCUIT 3 SINGLE POWER SUPPLY Vcc (6 ~ 12V) 3 8 1 + 2 LM358 4 5 8 7 + 6 LM358 4 0.1µF Vss Vcc L-OUT1 R-OUT1 + L-IN1 A-GND L-IN2 10µF Output (Left Channel) C3 Vcc Vcc + R-IN1 A-GND 10µF L-OUT2 R-OUT2 /INH U/D DCO OSC 10K Vcc 100K + 100µF - 14 - Output (Right Channel) C4 +4.7µF Up Key PT2253A V2.8 Input (Right Channel) C2 R-IN2 PT2253A 10K 10µF + C1 + 10µF Input (Left Channel) 1 IN4148 33K IN4148 2 1 2 2 2 2 2 + 1µ F December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A APPLICATION CIRCUIT 4 SINGLE POWER SUPPLY Vcc (6 ~ 12V) 3 8 1 + 2LM358 4 110K 0.15µF 51K 0.15µF 0.1µF Vss 68pF 51K 5 8 7 + 6LM358 4 110K 68pF Vcc L-OUT1 R-OUT1 C1 + L-IN1 A-GND L-IN2 10µF Output (Left Channel) Vcc C3 Vcc + R-IN1 A-GND Input (Right Channel) C2 R-IN2 10µF L-OUT2 R-OUT2 /INH U/D DCO OSC PT2253A 10K 10K 10µF + Input (Left Channel) + 10µF Vcc + Output (Right Channel) C4 4.7µF 100K + 100µF Up Key 1 IN4148 33K IN4148 2 1 2 2 2 2 2 + 1µ F Note: Since the buffer amp between Att-1 and Att-2 is already 10dB voltage gain, higher input level may cause OP amp’s output clipping. To avoid unwanted distortion, the input signal level applied at IN-1 should not be over 1Vrms. PT2253A V2.8 - 15 - December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A ORDER INFORMATION Valid Part Number PT2253A PT2253A-S PT2253A V2.8 Package Type 16 Pins, DIP, 300mil 16 Pins, SOP, 300mil - 16 - Top Code PT2253A PT2253A-S December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A PACKAGE INFORMATION 16 PINS, DIP, 300MIL PT2253A V2.8 - 17 - December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC Symbol A A1 A2 b b1 b2 b3 c c1 D D1 E E1 e eA eB eC L Min. 0.015 0.115 0.014 0.014 0.045 0.030 0.008 0.008 0.780 0.005 0.300 0.240 0.000 0.115 PT2253A Nom. 0.130 0.018 0.018 0.060 0.039 0.010 0.010 0.790 0.310 0.250 0.100 bsc 0.300 bsc 0.130 Max. 0.210 0.195 0.022 0.020 0.070 0.045 0.014 0.011 0.800 0.325 0.280 0.430 0.060 0.150 Notes: 1. Controlling Dimension: INCHES. 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 3. Dimensions A, A1 and L are measured with the package seated in JEDEC Seating Plane Gauge GS-3. 4. D, D1 and E1 dimensions do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010 inch. 5. E and eA measured with the leads constrained to be perpendicular to datum -C-. 6. eB and eA are measured at the lead tips with the leads unconstrained. 7. N is the maximum number of terminal positions (N=16). 8. Pointed or rounded lead tips are preferred to ease insertion. 9. b2 and b3 maximum dimensions do not include dambar protrusions. Dambar protrusions shall not exceed 0.010 (0.25mm). 10. Variation AB is a full lead package. 11. Distance between leads including dambar protrusions to be 0.005 in minimum. 12. Datum plane -H- coincident with the bottom of lead where lead exits body. 13. Refer to JEDEC MS-001 Variation AB. JEDEC is the registered trademark of JEDEC SOLID STATE TECHNOLOGY ASSOCIATION. PT2253A V2.8 - 18 - December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A 16 PINS, SOP, 300MIL Symbol A A1 B C D E e H h L α PT2253A V2.8 Min. Max 2.35 2.65 0.10 0.30 0.33 0.51 0.23 0.32 10.10 10.50 7.40 7.60 1.27 BSC 10.00 10.65 0.25 0.75 0.40 1.27 o 0 8o - 19 - December, 2005 Tel: 886-2-66296288 Fax: 886-2-29174598 URL: http://www.princeton.com.tw Electronic Volume Controller IC PT2253A Notes: 1. Controlling Dimension: MILLIMETER 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 3. Dimension D does not include mold flash, protrusions or gate burrs. Mold flash, protrusions and gate burrs shall not exceed 0.15mm (0.006 in) per side. 4. Dimension E does not include interlead flash or protrusions. Interlead flash and protrusions shall not exceed 0.25 mm (0.010 in.) per side. 5. The chamfer on the body is optional. If it is not present, a visual index feature must be located within the crosshatched area. 6. L is the length of the terminal for soldering to a substrate. 7. N is the number of terminal positions (N=16). 8. The lead width B, as measured 0.36 mm (0.014in) or greater above the seating plane, shall not exceed a maximum value of 0.61mm (0.024in.) 9. Refer to JEDEC MS-013 Variation AA. JEDEC is the registered trademark of JEDEC SOLID STATE TECHNOLOGY ASSOCIATION. PT2253A V2.8 - 20 - December, 2005