Ordering number : EN*5937 CMOS IC LC75386NE Electronic Volume and Tone Control for Car Stereo Systems Preliminary Overview Features The LC75386NE is an electronic volume and tone control IC that can implement a wide range of functions including volume, balance, fader, bass and treble controls, loudness, input switching, and input gain control with a minimal number of external components. • On-chip buffer amplifiers minimize the number of external components required. • The low level of switching noise generated from internal switches due to fabrication in a CMOS process minimizes switching noise when no input signals are present. • The use of built-in zero-cross switching circuits minimizes switching noise when input signals are present. • Built-in VDD/2 reference voltage generation circuit • All controls are controlled from CCB serial data input. Functions • Volume: • • • • • 0 to –79 dB ( in 1-dB steps) and –∞ for a total of 81 settings. A balance function can be implemented by controlling the left and right channel volume settings independently. Fader: The rear or the front outputs can be attenuated over 16 settings. (0 to –2 dB in 1-dB steps, –2 to –20 dB in 2 dB steps, –20 to –30 dB in 10-dB steps, –45 dB, -60 dB, and –∞ for a total of 16 settings.) Bass and treble: Control over a ±12-dB range in 2-dB steps in each band. Input gain: The input signal can be amplified from 0 to +18.75 dB (in 1.25-dB steps). Input switching: One of 6 inputs can be selected for each of the left and right channels. (Five are single-ended inputs, and one is a differential input.) Loudness: Taps are output from the –32-dB positions of the 2-dB step volume ladder resistors, and loudness operation can be implemented by attaching external capacitors. Package Dimensions unit: mm 3159-QFP64E [LC75386NE] SANYO: QFP64E • CCB is a trademark of SANYO ELECTRIC CO., LTD. • CCB is SANYO’s original bus format and all the bus addresses are controlled by SANYO. SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN 51298RM (OT) No. 5937-1/20 LC75386NE Pin Assignment Top view No. 5937-2/20 LC75386NE Equivalent Circuit and Application Circuit Diagram No. 5937-3/20 LC75386NE Specifications Absolute Maximum Ratings at Ta = 25°C, VSS = 0 V Parameter Symbol Conditions Maximum supply voltage VDD max VDD Maximum input voltage VIN max All input pins Operating temperature Storage temperature Ratings Unit 11 V VSS – 0.3 to VDD + 0.3 V Topr –40 to +85 °C Tstg –50 to +125 °C Allowable Operating Ranges at Ta = 25°C, VSS = 0 V Parameter Symbol Conditions Ratings min typ max Unit Supply voltage VDD VDD 6.0 10.5 High-level input voltage VIH CL, DI, CE 4.0 VDD V Low-level input voltage VIL CL, DI, CE VSS 1.0 V VSS VDD Vp-p Input amplitude VIN Input pulse width TøW V CL 1 µs µs Setup time Tsetup CL, DI, CE 1 Hold time Thold CL, DI, CE 1 Operating frequency fopg CL µs 500 kHz Electrical Characteristics at Ta = 25°C, VDD = 9 V, VSS = 0 V Input Block Parameter Input resistance Symbol Applicable pins Conditions Ratings min typ max Unit Rin L1 to L4, L6, R1 to R4, R6 35 50 65 Minimum input gain Ginmin L1 to L4, L6, R1 to R4, R6 –1 0 +1 dB Maximum input gain Ginmax +16.5 +18.75 +21 dB ATerr ±0.6 dB BAL ±0.5 dB Inter-step setting error Left/right balance kΩ Volume Control Block Parameter Input resistance Inter-step setting error Left/right balance Symbol Applicable pins Rvr LVRIN, RVRIN, Loudness off Conditions Ratings min 158 typ 226 max Unit 294 kΩ ATerr ±0.5 dB BAL ±0.5 dB Tone Control Block Parameter Symbol Applicable pins Conditions Ratings min typ Inter-step setting error ATerr Bass control range Gbass max. boost/cut ±9 ±12 Treble control range Gtre max. boost/cut ±9 ±12 Left/right balance BAL max Unit ±1.0 dB ±15 dB ±15 dB ±0.5 dB No. 5937-4/20 LC75386NE Fader Control Block Parameter Input resistance Symbol Rfed Applicable pins Conditions LFIN, RFIN Ratings min 25 typ max 50 0 dB to –2 dB Inter-step setting error Left/right balance ATerr 100 Unit kΩ ±0.5 dB –2 dB to –20 dB ±1 dB –20 dB to –30 dB ±2 dB –30 dB to –60 dB ±3 dB ±0.5 dB BAL Overall Characteristics Parameter Total harmonic distortion Inter-input crosstalk Left/right crosstalk Maximum attenuation Output noise voltage Symbol Conditions Ratings min typ max THD1 VIN = –10 dBV, f = 1 kHz 0.004 0.01 THD2 VIN = –10 dBV, f = 10 kHz 0.006 0.01 Unit % % CT VIN = 1 Vrms, f = 1 kHz 80 88 dB CT VIN = 1 Vrms, f = 1 kHz 80 88 dB Vomin1 VIN = 1 Vrms, f = 1 kHz 80 88 dB Vomin2 VIN = 1 Vrms, f = 1 kHz, INMUTE, Fader: –∞ 90 95 VN1 All flat, IHF-A filter VN2 All flat, 20 Hz to 20 kHz bandpass filter Current drain IDD High-level input current IIH CL, DI, CE, VIN = 9 V Low-level input current IIL CL, DI, CE, VIN = 0V –10 Maximum input voltage VCL THD = 1%, RL = 10 kΩ, All flat, fIN = 1 kHz 2.5 dB 5 10 µV 7 15 µV 33 40 mA 10 µA µA 2.9 Vrms Control System Timing and Data Format The LC75386NE is controlled by inputting stipulated data serially to the CL, DI, and CE pins. The data consists of a total of 52 bits, of which 8 bits are the address and 44 bits are the actual control data. Note*: The minimum value is determined by the value of the capacitor connected to the TIM pin (pin 20). If the value of the capacitor is CTIM and the minimum value is TDmin, then: TDmin = 3 × 103 × CTIM If CTIM is 0.033 µF, then: TDmin = 3 × 103 × 0.033 × 10–6 ≈ 100 µs No. 5937-5/20 LC75386NE • Address Code (B0 to A3) The LC75386NE has an 8-bit address code and can be used on a bus shared with other Sanyo ICs. Address Code (LSB) B0 B1 B2 B3 A0 A1 A2 A3 1 0 0 0 0 0 0 1 (81HEX) • Control code allocation Input Switching Control D0 D1 D2 0 0 0 L1 (R1) 1 0 0 L2 (R2) 0 1 0 L3 (R3) 1 1 0 L4 (R4) 0 0 1 L5 (R5) 1 0 1 L6 (R6) 0 1 1 1 1 1 D3 IC test values: These values must not be used during normal operation. IC test bit: This bit must be set to 0. Input Gain Control D4 D5 D6 D7 0 0 0 0 0 dB 1 0 0 0 +1.25 dB 0 1 0 0 +2.50 dB 1 1 0 0 +3.75 dB 0 0 1 0 +5.00 dB 1 0 1 0 +6.25 dB 0 1 1 0 +7.50 dB 1 1 1 0 +8.75 dB 0 0 0 1 +10.0 dB 1 0 0 1 +11.25 dB 0 1 0 1 +12.5 dB 1 1 0 1 +13.75 dB 0 0 1 1 +15.0 dB 1 0 1 1 +16.25 dB 0 1 1 1 +17.5 dB 1 1 1 1 +18.75 dB No. 5937-6/20 LC75386NE Volume Control D8 D9 D10 D11 D12 D13 D14 D15 1 dB step 0 0 dB 1 –1 dB 2 dB step 0 0 0 0 0 0 0 0 dB 1 0 0 0 0 0 0 –2 dB 0 1 0 0 0 0 0 –4 dB 1 1 0 0 0 0 0 –6 dB 0 0 1 0 0 0 0 –8 dB 1 0 1 0 0 0 0 –10 dB 0 1 1 0 0 0 0 –12 dB 1 1 1 0 0 0 0 –14 dB 0 0 0 1 0 0 0 –16 dB 1 0 0 1 0 0 0 –18 dB 0 1 0 1 0 0 0 –20 dB 1 1 0 1 0 0 0 –22 dB 0 0 1 1 0 0 0 –24 dB 1 0 1 1 0 0 0 –26 dB 0 1 1 1 0 0 0 –28 dB 1 1 1 1 0 0 0 –30 dB 0 0 0 0 1 0 0 –32 dB 1 0 0 0 1 0 0 –34 dB 0 1 0 0 1 0 0 –36 dB 1 1 0 0 1 0 0 –38 dB 0 0 1 0 1 0 0 –40 dB 1 0 1 0 1 0 0 –42 dB 0 1 1 0 1 0 0 –44 dB 1 1 1 0 1 0 0 –46 dB 0 0 0 1 1 0 0 –48 dB 1 0 0 1 1 0 0 –50 dB 0 1 0 1 1 0 0 –52 dB 1 1 0 1 1 0 0 –54 dB 0 0 1 1 1 0 0 –56 dB 1 0 1 1 1 0 0 –58 dB 0 1 1 1 1 0 0 –60 dB 1 1 1 1 1 0 0 –62 dB 0 0 0 0 0 1 0 –64 dB 1 0 0 0 0 1 0 –66 dB 0 1 0 0 0 1 0 –68 dB 1 1 0 0 0 1 0 –70 dB 0 0 1 0 0 1 0 –72 dB 1 0 1 0 0 1 0 –74 dB 0 1 1 0 0 1 0 –76 dB 1 1 1 0 0 1 0 –78 dB 1 1 1 1 1 1 0 –∞ 0 1 1 1 1 1 0 Inmute Mute No. 5937-7/20 LC75386NE Tone Control D16 D17 D18 D19 Bass D24 D25 D26 D27 Treble 0 1 1 0 +12 dB 1 0 1 0 +10 dB 0 0 1 0 +8 dB 1 1 0 0 +6 dB 0 1 0 0 +4 dB 1 0 0 0 +2 dB 0 0 0 0 0 dB 1 0 0 1 –2 dB 0 1 0 1 –4 dB 1 1 0 1 –6 dB 0 0 1 1 –8 dB 1 0 1 1 –10 dB 0 1 1 1 –12 dB D20 D21 D22 D23 0 0 0 0 These bits must be set to 0 Fader Volume Control D28 D29 D30 D31 0 0 0 0 0 dB 1 0 0 0 –1 dB 0 1 0 0 –2 dB 1 1 0 0 –4 dB 0 0 1 0 –6 dB 1 0 1 0 –8 dB 0 1 1 0 –10 dB 1 1 1 0 –12 dB 0 0 0 1 –14 dB 1 0 0 1 –16 dB 0 1 0 1 –18 dB 1 1 0 1 –20 dB 0 0 1 1 –30 dB 1 0 1 1 –45 dB 0 1 1 1 –60 dB 1 1 1 1 –∞ Channel Selection Control D32 D33 0 0 Initial setup mode: rapid charging 1 0 RCH 0 1 LCH 1 1 Left and right together No. 5937-8/20 LC75386NE Fader Rear/Front Control D34 0 Rear 1 Front Loudness Control D35 0 Off 1 On Zero Cross Control D36 D37 0 0 Data written when a zero crossing is detected 1 1 Zero cross detection disabled (Data is written when CE falls) Zero Cross Signal Detection Block Control D38 D39 D40 0 0 0 D41 0 Selector 1 0 0 0 Volume 0 1 0 0 Tone 1 1 0 0 Fader Test Mode Control D42 D43 0 0 This bit is used for IC testing and must be set to 0 No. 5937-9/20 LC75386NE Pin Descriptions Pin No. Pin name 54 L1 53 L2 52 L3 51 L4 55 L6 59 R1 60 R2 61 R3 62 R4 58 R6 50 L5M 49 L5P 63 R5M 64 R5P 48 LSEL0 1 RSEL0 47 LVRIN 2 RVRIN 46 LCT 3 RCT 45 LCOM 4 RCOM 43 LTIN 6 RTIN Function Notes • Single-ended inputs • Differential inputs • Input selector outputs • 2-dB step volume control inputs • Input signals must be provided from a low-impedance circuit. • Loudness connections. Connect the high-band compensation CR circuit between LCT (RCT) and LVRIN (RVRIN), and connect the low-band compensation CR circuit between LCT (RCT) and Vref. • 2-dB step volume control outputs • Connect these pins to Vref through coupling capacitors to reduce switching noise. • Equalizer inputs Continued on next page. No. 5937-10/20 LC75386NE Continued from preceding page. Pin No. Pin name 42 LF1C1 41 LF1C2 40 LF1C3 7 RF1C1 8 RF1C2 9 RF1C3 36 LF3C1 35 LF3C2 34 LF3C3 13 RF3C1 14 RF3C2 15 RF3C3 39 NC 38 NC 37 NC 10 NC 11 NC 12 NC 33 LTOUT 16 RTOUT Function • Connections for the capacitors that form the filters used for tone circuit low band. Connect capacitors between: LF1C1 (RF1C1) and LF1C2 (RF1C2), and between LF1C2 (RF1C2) and LF1C3 (RF1C3). • Connections for the capacitors that form the filters used for tone circuit high band. Connect capacitors between: LF3C1 (RF3C1) and LF3C2 (RF3C2), and between LF3C2 (RF3C2) and LF3C3 (RF3C3). • Unused pins. These pins are not connected to any part of the IC. • Equalizer outputs 32 LFIN • Fader block inputs 17 RFIN • These pins must be driven by low-impedance circuits. 31 LFOUT 30 LROUT 18 RFOUT 19 RROUT 57 Vref • A capacitor with a value of a few tens of µF must be connected between Vref and AVSS (VSS) to reduce power supply ripple in the VDD/2 voltage generation block. 56 VDD • Power supply 27 DVSS 29 LAVSS 22 RAVSS Notes • Fader outputs. The front and rear signals are attenuated separately. The amount of the attenuation is the same in the left and right channels. • Logic system ground • Analog system ground Continued on next page. No. 5937-11/20 LC75386NE Continued from preceding page. Pin No. Pin 28 LZCLP 21 RZCLP 23 MUTE Function Notes • Zero cross detector circuit band control • Externally controlled muting input • Setting this pin to the V SS level forcibly sets the fader volume block to the –∞ setting. • Time control for the zero cross circuit when no signal is present 20 TIM 26 CL 25 DI 24 CE 44 LVROUT 5 RVROUT If there is no zero cross signal between the point the data is loaded and the point the time defined by this pin elapses, the data is loaded forcibly. • Serial data and clock input for chip control • Chip enable. Data is written to the internal latch when this pin is switched from high to low, and the analog switches operate.Transfer data becomes enable when this pin is at high level. • 1-dB step volume control outputs No. 5937-12/20 LC75386NE Internal Equivalent Circuits Selector Block Equivalent Circuit Total resistance: 50 kΩ The right channel is identical. Unit (resistance: Ω) No. 5937-13/20 LC75386NE 2-dB Volume Control Block Equivalent Circuit To the left channel 1-dB block · Total resistance in the tap: 195 kΩ Initial settings switch The right channel is identical. Unit (resistance: Ω) · Total resistance in the tap: 30.847 kΩ No. 5937-14/20 LC75386NE 1-dB Volume Control Block Equivalent Circuit From the left channel 2-dB block Initial settings switch Initial settings switch Unit (resistance: Ω) Total resistance: 50 kΩ The right channel is identical. Tone Control Block Equivalent Circuit Unit (resistance: Ω) No. 5937-15/20 LC75386NE External Capacitor Calculations The LC75386NE external capacitors are the structural components in semiconductor inductors, i.e. simulated inductors. This section presents the equivalent circuit and the formulas used to calculate the desired center frequencies. Semiconductor inductor equivalent circuit Z0: Impedance at resonance Sample calculation Specifications: 1. Center frequency: F0 = 100 Hz 2. Q at maximum boost: Q+12dB = 0.9 • Determine the sharpness, Q0, of the semiconductor inductor. (R1 + R4) Q0 = ————— × Q+12dB ≈ 1.53999 R1 • Determine C1. C1 = 1/2π FOR1QO ≠ 1 (µF) • Determine C2. C2 = QO/2π FOR2 ≠ 0.036 (µF) Note: See the tone control block equivalent circuit diagram in page 15 for the internal resistance. No. 5937-16/20 LC75386NE Fader Volume Control Block Equivalent Circuit When FADER = 1, S2 and S3 will be on. When FADER = 0, S1 and S4 will be on. Unit (resistance: Ω) Total resistance: 50 kΩ If data corresponding to a –∞ is send to the 1-dB step main volume, S1 and S2 will be set open and S3 and S4 will be turned on at the same time. No. 5937-17/20 LC75386NE Usage Notes • Notes on data transfer when power is first applied — The states of the internal analog switches are undefined when power is first applied. Until the control data has been set up, applications must mute signals appropriately. — Applications should send initial setup data to quickly stabilize the bias levels in each block when power is first applied. • The period between initial setup mode and initial data setup — Applications should transfer the initial setup data after the power-supply voltage VDD exceeds 6 V. — Send initial data (that turns the rapid charging switches off) after the LCOM, RCOM, and VREF pin levels have stabilized. Time until the capacitors connected to the LCOM and RCOM pins are charged to the VREF level. 1/2 VDD level Data Initial setup mode Initial data (left channel) Initial data (right channel) These operations clear initial setup mode • Procedure for transferring the initial setup data Quick charge mode is set up when D32 and D33 are set to 00. Since the other data (D0 to D31, and D34 to D43) is set up for the left and right channels at the same time, the states of the other blocks can be set at the same time. • Procedure for clearing the initial setup data Quick charge mode is cleared when D32 and D33 are set to a value other than 00, that is when normal left/right channel operation is specified. Operating Principles of the Zero Cross Switching Circuit The LC75386NE provides a function that switches the signal detection location of the zero cross comparator. This means an optimal location for block for data update can be selected. Basically, switching noise can be minimized by inputting the signal from immediately after the block that modifies the data to the zero cross comparator. Therefore, the detection location needs to be changed each time the IC control settings are changed. Selector Volume Tone Fader Switch Zero cross comparator Zero Cross Detection Circuit No. 5937-18/20 LC75386NE Zero Cross Switching Control Zero cross switching is controlled by setting the zero cross control bits to zero cross detection mode (by setting both D36 and D37 to 0), specifying the detection block (with bits D38, D39, D40, and D41), and transferring the data. Since these control bits are latched immediately after the data is transferred, that is, on the falling edge of the CE signal, when volume and other setting data is changed, it is possible to also set the mode and the zero cross operation at the same time in a single data transfer operation. The example below shows a control pattern that can be used at the same time as the volume setting data is updated. D36 D37 D38 D39 D40 D41 0 0 1 0 0 0 Zero cross detection Volume block setting mode setting Zero Cross Timer Setting When the level of the input signal is lower than the zero cross detector sensitivity setting, or when the input signal is a low-frequency signal, the system will remain in a state where it cannot detect a zero cross event for an extended period, and the IC will not be able to latch data during that period. The zero cross timer sets a period for forcibly latching the data when the IC is in a state such as this where a zero cross cannot be detected. For example, to set a time of 25 ms: T = 0.69 × C × R If C = 0.033 µF, then: 25 × 10–3 R = ————————— ≈ 1.1 MΩ 0.69 × 0.033 × 10–6 This time is normally set to be in the range 10 to 50 ms. Notes on Serial Data Transfer • The CL, DI, and CE pin signal lines must be covered by the ground pattern, or shielded cables must be used for these lines, to prevent high-frequency noise from these signals from entering the audio signal. • The LC75386NE data format consists of 8 bits of address and 44 bits of data. Use the data transfer format shown in the figure below when transmitting data in multiples of 8 bits (i.e. when sending 48 bits of data). Data Transfer to the LC75386NE in 8-Bit Units Dummy data Input switching control Test mode control No. 5937-19/20 LC75386NE ■ No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or indirectly cause injury, death or property loss. ■ Anyone purchasing any products described or contained herein for an above-mentioned use shall: ➀ Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated with such use: ➁ Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally. ■ Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. This catalog provides information as of May, 1998. Specifications and information herein are subject to change without notice. PS No. 5937-20/20