PT2258 6-Channel Electronic Volume Controller IC DESCRIPTION PT2258 is a 6-Channel Electronic Volume Controller IC utilizing CMOS Technology specially designed for the new generation of AV Multi-Channel Audio System. PT2258 provides an I2C Control Interface, an attenuation range of 0 to -79dB at 1dB/step, low noise, and high channel separation. Housed in 20 pins, DIP or SOP, PT2258’s pin assignments and application circuit are optimized for easy PCB Layout and cost saving advantages. APPLICATIONS FEATURES CMOS Technology Low Power Consumption Least External Components Attenuation Range: 0 to -79dB at 1dB/step Operating Voltage: 5 to 9 V Low Noise, S/N Ratio>100dB (A-weighting) High Channel Separation I2C Bus Control Interface Selectable Address 6-Channel Outputs Available in 20 pins, DIP or SOP AV Surround Audio Equipment Car Audio Mini Compo Computer Multi-Media Speaker Other Audio Equipments BLOCK DIAGRAM Tel: 886-66296288‧Fax: 886-29174598‧ http://www.princeton.com.tw‧2F, No.233-1, Baociao Rd., Sindian Dist., New Taipei City 23145, Taiwan PT2258 APPLICATION CIRCUIT V1.3 2 March 2014 PT2258 ORDER INFORMATION Valid Part Number Package Type Top Code PT2258 PT2258-S 20 Pins, DIP, 300mil 20 Pins, SOP, 300mil PT2258 PT2258-S PIN CONFIGURATION V1.3 3 March 2014 PT2258 PIN DESCRIPTION V1.3 Pin Name I/O Description IN1 I IN2 I IN3 I CODE2 DGND SCL SDA I I IN4 I Channel Input No. 4 Connect a Capacitor to Audio Source 8 IN5 I Channel Input No. 5 Connect a Capacitor to Audio Source 9 IN6 I Channel Input No. 6 Connect a Capacitor to Audio Source 10 OUT6 O Channel Output No. 6 Connect a Capacitor to the Next Stage 11 OUT5 O Channel Output No. 5 Connect a Capacitor to the Next Stage 12 OUT4 O Channel Output No. 4 Connect a Capacitor to the Next Stage 13 GND - REF - VCC CODE1 - OUT3 O OUT2 O OUT1 O Channel Input No. 1. Connect a Capacitor to Audio Source Channel Input No. 2 Connect a Capacitor to Audio Source Channel Input No. 3 Connect a Capacitor to Audio Source Refer to Address Code Section Digital Ground 2 I C Clock Input 2 I C Data Input Ground 14 Reference Voltage= 1/2 Vcc Connect a Capacitor to the Ground Power Supply Input 16 Refer to the Address Code Section Channel Output No. 3 Connect a Capacitor to the Next Stage Channel Output No. 2 Connect a Capacitor to the Next Stage Channel Output No. 1 Connect a Capacitor to the Next Stage 4 Pin No. 1 2 3 4 5 6 7 14 15 16 17 18 19 20 March 2014 PT2258 FUNCTIONAL DESCRIPTION BUS INTERFACE Data are transmitted to and from the microprocessor to the PT2258 via the SDA and SCL. The SDA and SCL make up the BUS Interface. It should be noted that the pull-up resistors must be connected to the positive supply voltage. DATA VALIDITY A data on the SDA Line is considered valid and stable only when the SCL Signal is in HIGH State. The HIGH and LOW States of the SDA Line can only change when the SCL signal is LOW. Please refer to the figure below. START AND STOP CONDITIONS A Start Condition is activated when 1) the SCL is set to HIGH and 2) SDA shifts from HIGH to LOW State. The Stop Condition is activated when 1) SCL is set to HIGH and 2) SDA shifts from LOW to HIGH State. Please refer to the timing diagram below. BYTE FORMAT Every byte transmitted to the SDA Line consists of 8 bits. Each byte must be followed by an Acknowledge Bit. The MSB is transmitted first. V1.3 5 March 2014 PT2258 ACKNOWLEDGE During the Acknowledge Clock Pulse, the master (µP) puts a resistive HIGH level on the SDA Line. The peripheral (audio processor) that acknowledges has to pull-down (LOW) the SDA line during the Acknowledge Clock Pulse so that the SDA Line is in a Stable Low State during this Clock Pulse. Please refer to the diagram below. The audio processor that has been addressed has to generate an Acknowledge after receiving each byte, otherwise, the SDA Line will remain at the High Level during the ninth (9th) Clock Pulse. In this case, the master transmitter can generate the STOP Information in order to abort the transfer. TRANSMISSION WITHOUT ACKNOWLEDGE If you want to avoid the acknowledge detection of the audio processor, a simpler µP transmission may be used. Wait one clock and do not check the slave acknowledge of this same clock then send the new data. If you use this approach, there are greater chances of faulty operation as well as decrease in noise immunity. INTERFACE PROTOCOL The interface protocol consists of the following: A Start bit A Chip Address Byte ACK=Acknowledge bit A Data byte A Stop bit Please refer to the diagram below: Notes: 1. ACK = ACKNOWLEDGE 2. MAX. CLOCK SPEED = 100K BITS/S V1.3 6 March 2014 PT2258 PT2258 ADDRESS CODE PT2258 Address Code depends on the state of CODE1 (Pin No.17) and CODE2 (Pin No.4). If CODE1 or CODE2 is connected to Vcc, then CODE1 or CODE2 is set to “1”. If CODE1 or CODE2 is connected to the Ground, it is set to “0”. Please refer to the information below: Condition 1: CODE1 1 CODE2 1 Then, PT2258 Address Code is 8 CH: 1 MSB Condition 2: CODE1 1 0 0 0 1 1 0 0 LSB 0 1 0 0 0 LSB 0 0 1 0 0 LSB 0 0 0 0 0 LSB CODE2 0 Then, PT2258 Address Code is 88 H: 1 MSB Condition 3: CODE1 0 0 0 CODE2 1 Then, PT2258 Address Code is 84 H: 1 MSB Condition 4: CODE1 0 0 0 CODE2 0 Then, PT2258 Address Code is 80H: 1 MSB V1.3 0 0 7 March 2014 PT2258 I2C BUS INTERFACE START TIME After Power is turned ON, PT2258 needs to wait for a short time in order to insure stability. The waiting time period for 2 2 PT2258 to send I C Bus Signal is at least 200ms. If the waiting time period is less than 200ms, I C Control may fail. Please refer to the diagram below. V1.3 8 March 2014 PT2258 PT2258 CONTROL SOFTWARE PROCEDURE 1. In order to ensure exact operation under any operating voltage, it is recommended an instruction to clear the register “C0H” must be transmitted first. Please refer to the following diagram: Start 1 0 0 0 1 2258 Address 0 0 0 Ack 1 1 0 0 Clear Register 0 0 0 0 Ack Stop 2. The PT2258 function register does not have any default settings. After clearing the register, an initial value must send in order to each register. If a register does has not been set, it is possible that no sound will be output. 3. When adjusting the volume of PT2258, it is necessary to send a multiple of 10dB followed by a 1dB code to the attenuator in sequence. If this sequence is not followed, or if only a 10dB or 1dB value is sent, the IC may not operate normally. Please refer to the diagram below: Volume setting -42dB： Start 1 0 0 0 1 0 0 0 Ack 1 1 0 1 0 1 0 0 PT2258 Address -40dB Start 1 0 0 0 1 0 0 0 Ack 1 1 1 0 0 0 1 0 PT2258 Address -2dB The two methods above are both acceptable. ACK Ack 1 1 1 0 0 0 1 0 Ack -2dB 1 1 0 1 0 1 0 0 ACK -40dB Stop Stop Warning!! The following transmission method is not permitted. Send only a 10dB attenuation value: Start 1 0 0 0 1 0 PT2258 Address 0 0 Ack 1 -40dB 1 0 1 0 1 0 0 ACK Stop Send only a 10dB attenuation value: Start 1 0 0 0 1 0 PT2258 Address 0 0 Ack 1 -2dB 1 1 0 0 0 1 0 ACK Stop Do not send a 10dB code without simultaneously with a 1dB code or in combination with other instruction codes. Start V1.3 1 0 0 0 1 0 0 0 Ack 1 1 1 0 0 0 1 0 Ack 1 1 1 1 1 0 0 1 ACK 1 1 0 1 0 1 0 0 ACK PT2258 Address -2dB All CH mute -40dB 9 Stop March 2014 PT2258 DATA BYTES DESCRIPTION FUNCTION BITS MSB LSB FUNCTION 1 1 0 0 0 0 1 1 0 0 0 0 1 0 0 0 1 1 0 1 1 0 1 0 A3 0 A3 0 A3 0 A2 B2 A2 B2 A2 B2 A1 B1 A1 B1 A1 B1 A0 B0 A0 B0 A0 B0 6-Channel, -1dB/step 6-Channel, -10dB/step Channel No. 3, -1dB/step Channel No. 3, -10dB/step Channel No. 4, -1dB/step Channel No. 4, -10dB/step 0 0 0 0 1 1 1 1 1 1 0 0 0 0 1 1 0 0 1 0 1 0 1 0 A3 0 A3 0 A3 0 A2 B2 A2 B2 A2 B2 A1 B1 A1 B1 A1 B1 A0 B0 A0 B0 A0 B0 Channel No. 2, -1dB/step Channel No. 2, -10dB/step Channel No. 5, -1dB/step Channel No. 5, -10dB/step Channel No. 1, -1dB/step Channel No. 1, -10dB/step 1 1 0 0 1 1 1 0 A3 0 A2 B2 A1 B1 A0 B0 Channel No. 6, -1dB/step Channel No. 6, -10dB/step 1 1 1 1 1 0 0 M 6-Channel, Mute When M= 1, MUTE ON When M=0, MUTE OFF ATTENUATION UNIT BIT A3/--- A2/B2 A1/B1 A0/B0 Attenuation Value(dB) 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 1 1 0 0 1 0 1 0 1 0 1 0 0/0 -1/-10 -2/-20 -3/-30 -4/-40 -5/-50 -6/-60 0 1 1 1 0 0 1 0 0 1 0 1 -7/-70 -8/----9/---- Note: Ax=-1dB/step, Bx=-10dB/step V1.3 10 March 2014 PT2258 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Ratings Unit Vs Topr Supply Voltage Operation Temperature 12 V -40～+85 ℃ Tstg Storage Temperature -65～+150 ℃ ELECTRICAL CHARACTERISTICS (VDD=9V, VI=1Vrms, f=1 KHz, Temp=27℃) Symbol Parameter Conditions Min. Typ. Max. Unit 5 7 9 10 10 12 V mA 22 33 42 KΩ 2.8 100 79 -79 1 3.0 110 Vrms dB dB dB dB VDD Is Supply Voltage Supply Current RIN Input Impedance FL, FR, CTR, SUB, SL, SR VCL Sc Crange Avmax Astep Max. Input Voltage Channel Separation Volume Control Range Max. Attenuation Attenuation Step Volume=0dB, THD=1% EA Attenuation Error Volume=0～-50dB -1.0 0 +1.0 dB AMUTE THD Mute Attenuation Total Harmonic Distortion A-weighting Volume=0dB, input 200mVrms 90 0.003 95 0.005 98 0.01 dB % Noise Output Noise A-weighting 3 5 μV S/N Signal-Noise Ratio 0dB=1Vrms, A-weighting 105 110 dB Ro Output Impendance 600 900 Ω Go Output Gain -0.5 0 +0.5 dB 2.3 2.5 2.8 Vrms 2.4 3.0 2.5 2.8 V V 250 300 mS Vomax Max. Output Voltage 90 FL, FR, CENTER, SUB, SL, SR THD=1% 100 2 I C Section VIL VIH Bus Low Input Level Bus High Input Level TINIT Bus Initialization V1.3 Cref=10μF 11 March 2014 PT2258 PACKAGE INFORMATION 20 PINS, DIP, 300MIL Symbol A A1 A2 b c D E E1 e L Min. 0.38 2.92 0.36 0.20 24.89 6.10 2.92 Dimensions (mm) Nom. 3.30 26.16 7.62BSC 6.35 2.54BSC - Max. 5.33 4.95 0.56 0.36 26.92 7.11 3.81 Notes: 1. Refer to JEDEC MS-001, Variation BA 2. All dimensions are in millimeter V1.3 12 March 2014 PT2258 20 PINS, SOP, 300MIL Symbol A A1 b c e D E E1 L θ Dimensions(mm) Nom. 1.27 BSC 12.80 BSC 10.30 BSC 7.50 BSC - Min. 0.10 0.31 0.20 0.40 0° Max. 2.65 0.30 0.51 0.33 1.27 8° Notes: 1. Refer to JEDEC MS-013AC 2. All dimensions are in millimeter V1.3 13 March 2014 PT2258 IMPORTANT NOTICE Princeton Technology Corporation (PTC) reserves the right to make corrections, modifications, enhancements, improvements, and other changes to its products and to discontinue any product without notice at any time. PTC cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a PTC product. No circuit patent licenses are implied. Princeton Technology Corp. 2F, 233-1, Baociao Road, Sindian Dist., New Taipei City 23145, Taiwan Tel: 886-2-66296288 Fax: 886-2-29174598 http://www.princeton.com.tw V1.3 14 March 2014