HC34018 Voice Switched Speakerphone Circuit for Hand Free System HSiN Semiconductor Pte Ltd www.hsin.com.sg 1. Overview The HC34018 speakerphone integrated circuit incorporates the necessary amplifiers attenuators and control functions for a high quality hands-free speakerphone system. Included are microphone amplifier, audio power Amp for speaker, transmit and receive attenuator, a monitoring system for background noise level and an attenuation control system which responds to the relative transmit and receive level as well as background level. Also included are voltage regulator circuits both for internal and external circuit. A Chip Select pin allows the chip to be powered down when not in use. The CSC34018CP applications include speakerphone for household and business use, intercom system, automotive telephones and others. Its features are: All necessary level detection and attenuation control for hands-free telephone in one single chip Background level monitoring with long time constant Wide dynamic operating range with through signal compression On-chip supply and reference voltage regulation Typical 100mW output into 25 load and peak level limiting to reduce distortion Chip Select pin for active/standby switch Linear volume control 13 10 12 25 11 Microphone Amp 2 23 3 Transmit ATT 9 4 Transmit Level DET Noise Signal DET 17 ATT CONT. 6 TX RX Comparator 8 Receive Level DET Peak Limiter 5 7 26 Receive ATT 15 27 Speaker Amp 14 22 19 Vcc REG 24 1 28 16 Page 1 of 6 18 20 21 2. 2 Pin Description Pin No. 1 Symbol CONAA 2 CONATA 3 4 INTA OUTTA 5 INTD 6 OUTTD 7 INRD 8 OUTRD 9 10 11 12 13 14 INMC OUTMC CMPNV CMPTV INCMP GNDP Description Pin No. ATT Gain Control 15 Transmit ATT 16 Gain Control Transmit ATT Input 17 Transmit ATT Output 18 Transmit Level 19 Detector Input Transmit Level 20 Detector Output Receive Level 21 Detector Input Receive Level 22 Detector Output Microphone Input 23 Microphone Output 24 Noise Level Compare 25 Signal Level Compare 26 Comparator Input 27 Power Ground 28 Symbol OUTP Description Power Output Input DC Supply Voltage Power AGC Control Digital Chip Select Input V+ AGCP EN INP Power Input REG Regulation Bias Voltage VB GND Ground OUTCMP CONVOL FILAC IUTRA INRA CONARA Comparator Output Volume Control ATT Control Filter Receive ATT Output Receive ATT Input Receive ATT Gain 3. Electrical Characteristics 3. 1 Absolute Maximum Ratings Unless otherwise specified, Tamb= 25 Parameter V+ Terminal Voltage Chip Select Terminal Voltage Speaker Power Ground Voltage Volume Control Terminal Voltage Operating Temperature Storage Temperature Symbol V+ VEN V14 VCON Tamb Tstg Value 12/-1.0 12/-1.0 3.0/-1.0 VCC/-1.0 -20 ~ 70 -65 ~ 150 Unit V V V V 3. 2 Recommended Operating Conditions Parameter Symbol V+ Terminal Voltage Chip Select Terminal Voltage Internal Regulation Current Volume Control Terminal Voltage Receive ATT Input Signal Voltage Microphone Amp Input Signal Voltage Speaker Power Ground Voltage V+ VEN ICC Recommended Conditions Min 6.0 0 0 Value Typ Max 11 11 3.0 Unit V V mA 0.55 VB VIIRA 0 250 mV VIMC 0 5.0 mV V14 -10 10 mV VCON Page 2 of 6 V 3.3 Electrical Characteristics Unless otherwise specified, Tamb= 25 , add supply voltage on pin 22, V+=7.5V, VEN=0.7V. Receiving Mode: V8=5V; Transmitting Mode: V6=5V, V11=0V Standby Mode: V6=5V, V11=5V Parameter Symbol Test Conditions Min Value Typ Max Unit Supply Voltage Supply Current VCC Voltage Line Regulation Output Resistance Dropout Voltage VB Voltage Output Resistance Receive Attenuators ATT Gain Range Idle Mode IV+ VCC VCCLIN RO(VCC) Vsat VB RO(VB) ARA ARA ARAI Receive Output Voltage Delta OUTRA OUTRA Sink Current OUTRA Source Current Input Resistance VRAO VRAO ARAOL IRAOH RRAOH Volume Control VCON V =11V, V18=0.7V V =11V, V18=1.6V V =7.5V 6.5V V+ 11V ICC=3.0mA V =5.0V V =7.5V VB, IB=1.7ma Receive, f=1.0kHz V24=VB, V27=250mV Receive to Transmit Receive, f=1.0kHz V24=VB V27=250mV Receive Receive to Transmit Receive Receive Receive Receive 0.6VB V24 VB 4.9 2.5 5.4 65 6.0 80 2.9 250 9.0 800 5.9 150 20 300 3.3 mA uA V mV mV V 2.0 6.0 10 dB 40 44 48 dB -20 -16 -12 dB 1.8 2.3 3.2 100 75 1.0 3.5 5.0 3.0 8.0 V mV uA mA k 32.5 dB 24.5 Transmit Attenuators ATT Gain Range Idle Mode Transmit Output Voltage Delta OUTRA OUTRA Sink Current OUTRA Source Current Input Resistance FILAC Terminal Voltage ATA ATA ATAI VOTA VRAO ATAOL ITAOH RTAI VACF Power Amplifier for Speaker Gain AP Input Resistance RIP Output Voltage VOP Output High Level VPOH Output Low Level VPOL Transmit f=1.0kHz V3=250mV Transmit to Receive Standby f=1.0kHz, V3=250mV Transmit Transmit to Receive Transmit Transmit 4.0 6.0 8.0 dB 40 44 48 dB -16.5 -13 -8.5 dB 1.8 2.3 3.2 100 3.0 8.0 V mV uA mA k mV mV mV 75 1.0 3.5 Receive Transmit Standby V19=20mV V19 with capacitor to GND V19=0.1V, V15=-100mA V19= -0.1V, V15=100mA Page 3 of 6 5.0 150 6.0 75 33 15 34 22 35 37 dB k 2.4 3.0 3.6 V 5.5 V 600 mV Parameter Symbol Speaker Amplifier Amp Gain Input Resistance LOGAMPS Receive Leakage Current Transmit Leakage Current Transmit to Receive Threshold Transmit Detector Comparator Output Voltage CP2 Current Source Distortion Test Conditions AMC RIMC V9=10mV, f=1.0kHz Min Value Typ Max 32.5 6.5 34 10 35 16 dB k Unit ILKORD V8=VB -1.0V 2.0 uA ILKOTD V6=VB-1.0V 2.0 uA Ratio of ITLI to IRLI at 20 uA ITH 0.8 Idle Transmit VCCMP ICP2 Transmit Distortion DRA Receive Distortion DTA 1.2 0 4.0 10 5.0 V INR to OUTP V27=10mVrms,1kHz INMC to OUTTA V9=5.0mVrms,1kHz 13 uA 1.5 % 2.0 % 4. Test Circuit OUT MC Vcc V+ 1000uF 47uF 200k 100k 47k + 12 + 0.1uF 13 4.7uF 23 11 18 IN 16 9 47uF + IN MC 10 + SW1 + 4.7uF 0.068uF 20 3.3k 5 22 0.068uF 6 + 2.2M 1uF 17 7 4 27 26 19 14 18k SW2 30k + 28 0.047uF 1 4.3k 2 0.1uF 3 91k VB 25 0.1uF 47uF 2.2M + 1uF 0.0068uF 4.7k + 24 47uF 21 18k 8 24k IN RA OUTTA Page 4 of 6 + 47uF 25 0.01uF VB 1uF 15 OUTp /1W Max Gain Vacf=6.0mV +10 0 -10 Max Att -20 Vacf=150mV -30 RR=30k -40 Vcc=V B -50 -60 -70 dB dB 5. Characteristics Curve 10k +10 Max Gain 0 Vacf=150mV -10 -20 -30 -40 RR=30k -50 Vcc=V B -60 -70 1M 100k Max Att Vacf=6.0mV 10k 0.5 0.1 dB dB GTX Vs.RTXRR +10 Vacf=6.0mV 0 -10 -20 GRX Vs.RRXRR -30 Vacf=150mV -40 -50 ARX Vs.RRXRR -60 Vacf=6.0mV -70 1M 100k RRX RTX ATX Vs.RTXRR Vacf=150mV 1.0 Ratio 5.0 RRX=18K +5 RTX=91K 0 RR=30K -5 -15 Circuit in -20 Receive Mode -25 -30 -35 -40 GTX GRX Min Recommanded Level 0.2 10 0.8 0.4 0.6 Vcc/V B 0 20 200 GRX RLO.TLO(mV) dB 250 +5 GTX 0 -5 RRX=18K -15 RTX=91K -20 RR=30K -25 -30 -35 -40 40 60 80 100 120 Vacf(mV) 0 140 160 30 VSKO MAX(Vp_p) (RLO.TLO) 2.2uF RLO.TLO.CPI(mV) R=4700 C=0.068uF IN RLI.TLI I C R (1.0KH) VB 10 (RLI.TLI.XLI) -20 (RLO.TLO.CPL) OUT Vo TAGE -40 -60 RLI.TLI.XDI.(uA) -80 10 90 0 IN I VB R=2700 120 C=0.1uF 30 100 50 150 60 150 2.2M 50 8.0 No Load 6.0 25 4.0 Load 2.0 0 70 4.0 5.0 6.0 7.0 8.0 V+(V) RLI.TLI(mVp-p) Page 5 of 6 9.0 10 11 1.0 6. Application Circuit TIP 0.05uF B 4.7k IN4007X4 68k 27k SW1 RING 470k VB Vcc 47uF 2.0k 47uF 3 10 100k 4.7k + + + 13 4 5 11 2 1 28 26 4.7uF SW2 0.068uF 0.1uF 0.068uF MIC 22k 0.001uF 470k 1000uF 15k 7.5V IN4737 3.3k VB 0.05uF 0.0047uF 47k 27 0.068uF 2.2k 0.068uF 8.2k + 10uF 47k 10k 470k 0.1uF 68k 0.01uF 1M 47k 33k 0.01uF 0.001uF 25 1.0uF 17 4.7k 0.1uF 16 18 7 27 8 22 9 15 0.01uF 7. Package Dimensions Page 6 of 6 6 2.2M + 23 + + + 1.0uF 12 200k 4.3k 18k 30k 24k 91k 20k 47uF 47uF VB + 19 4.7uF 20 4.7uF 21 + 47uF 24 0.05uF 14 25 2.2M