AMBE-2000 Digital Voice Systems, Inc., AMBE-2000 Datasheet
AMBE-2000
Available stocks
Related parts for AMBE-2000
AMBE-2000 Summary of contents
Page 1
... Digital Voice Systems, Inc. The Speech Compression Specialists AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 January 2003 ...
Page 2
... The information in this document is subject to change without notice. Trademarks AMBE-2000™ Vocoder Chip is a registered trademark of Digital Voice Systems, Inc. Other product names mentioned may be trademarks or registered trademarks of their respective companies and are the sole property of their respective manufacturers. ...
Page 3
... Voice Compression Software contained in the AMBE-2000™ Vocoder Chip. 3.0 Transfer of License 3.1 The END USER shall have the right to transfer the AMBE-2000™ Vocoder Chip and all rights under this Agreement to a third party by either (i) providing the third party with a copy of this Agreement or (ii) providing the third party with an agreement written by the END USER ( hereinafter “ ...
Page 4
... Product Introduction 1.1 General Information 1.2 Advantages 1.3 Typical Applications 2. AMBE-2000™ Application Design Overview 2.1 Basic Operation 2.2 Initial Design Considerations 2.2.1 A/D – D/A Overview 2.2.2 Vocoder Front End Requirements 2.2.3 Channel Interface Overview 2.2.4 Speech and FEC Rate Selection Overview 3 Hardware Information 3.1 Special Handling Instructions 3.1.1 Storage 3.2 Pin Descriptions 3.3 Clock and Reset Timing 3 ...
Page 5
... Configuring the AD73311 for 3-Volt Operation 8.4 Interfacing to the Texas Instruments PCM3500 Codec 8.5 Expanded Tone Detection and Generation 8.6 Soft Decision Decoding DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4 ...
Page 6
... Correction) data rates. The user can separately select these parameters in 50 bps increments for total rates from 2.0 kbps to 9.6 kbps. Typically for higher error rate channels, the user will apportion a greater percentage of the total bit rate to FEC coding. The AMBE-2000™ voice coder maintains natural voice quality and speech intelligibility at rates as low as 2.0 kbits/sec. The ...
Page 7
... Satellite Communications • Digital Mobile Radio • Secure Communications • Cellular Telephony and PCS • Voice Multiplexing • Voice Mail • Multimedia Applications DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Page 7 ...
Page 8
... AMBE-2000™ Application Design Overview 2.1 Basic Operation In its simplest model, the AMBE-2000™ can be viewed as two separate components, the Encoder and the Decoder. The Encoder receives an 8kHz sampled stream of speech data (16-bit linear, 8-bit Alaw, or 8-bit ulaw) and outputs a stream of channel data at the desired rate. Conversely the Decoder receives a stream of channel data and synthesizes a stream of speech data. The timing for the interfaces for the AMBE-2000™ ...
Page 9
... A- to-D converter -18 dB - 200 400 DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Vocoder Front End Analog Digital A-to-D Input Input Convertor Filter Gain Analog Digital ...
Page 10
... The serial port can run in passive or active modes. In passive mode, all of the channel interface control signals are inputs to the AMBE-2000™ chip. In active mode, only the TX_DATA_STRB is an output from the AMBE-2000™ chip. All other signals are inputs. ...
Page 11
... Chip to run in Passive or Active modes. In Passive mode, data strobes are provided by an external source, while in Active mode, data strobes are provided by the AMBE-2000™ Vocoder Chip. The serial interfaces can be run in Passive or Active modes. See Section 4 for full details and timing for both Framed and Unframed data. ...
Page 12
... The 100 pin TQFP package design of the AMBE-2000™ Vocoder Chip allows mounted by infrared reflow, vapor- phase reflow or equivalent processes. The peak package body temperature must not exceed 220°C. ...
Page 13
... Output from internal oscillator for the crystal. If the internal oscillator is not used this pin Input should be unconnected. Input AMBE-2000™ Reset pin. Active LOW. See Section 3.3 Encode Packet Ready: Following a reset, this signal will have a high to low transition to Output indicate the first packet is ready. The next packet will be ready approximately 20 msec later ...
Page 14
... Note 1:The AMBE-2000™ expects an encoder packet to be read approximately every 20 msec. Following the initial reset, wait for EPR to go low and read the initial packet (t0). 20 msec later, the next packet (t1) should be ready. For packet t1 and all following packets use the procedure below: 1) Wait for slightly less than 20 msec ...
Page 15
... Clock and Reset Timing To reset the AMBE-2000 chip, the reset signal must be held low for a minimum of 50 µs. The recovery time from reset is approximately 95 ms. In other words after the rising edge of the reset signal the AMBE-2000™ starts processing PCM samples ...
Page 16
... Setup time, INTn, NMI, RS before CLKOUT low su • CLKOUT is shown for reference only. It should not be connected in the circuit. DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Parameter Integer PLL multiplier N (N=4) t (CI)/ (RS) ...
Page 17
... Crystal / Oscillator Usage The AMBE-2000™ Vocoder Chip has an input clock frequency of 16.384 MHz. Two options are outlined below in providing this signal. The CLOCK_MODE pin 51 must be set appropriately for the option used. The following points should be noted when designing any printed circuit board layout: • ...
Page 18
... X2/CLKIN and X1 along with one external capacitor from each of these pins to ground. The recommended value for C1 and pF. Figure 3-D X2/CLKIN and X1 with Crystal Oscillator DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4 X2/CLKIN (pin 68) AMBE-2000 16.384 MHz ...
Page 19
... Package Description 100 pin TQFP (Thin Quad Flat Pack) All Dimensions are in millimeters Figure 3-E Package Dimensions 76 100 DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 16.20 / 15.80 SQ 14.20 / 13.80 SQ 12.00 TYP All Around 0.5 mm 0.17 / 0.27 1.35 /1.45 1.60 MAX 0.05 0.25 Not Drawn to Scale ...
Page 20
... Output capacitance O † All values are typical unless otherwise specified. DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Normal Operating Conditions Operating Voltage Operating Case Temperature Range Storage Temperature Range Absolute Maximum Ratings ...
Page 21
... It is important to realize that not all data being output from the AMBE-2000™ is intended for transmission over the channel. Status type of data is typically only useful at the ‘local’ end. In most voice transmission systems, the actual encoded bits are extracted from the channel formatting, combined into the systems transmission stream, sent over the transmission path, extracted from the transmission path at the receiving end, and reassembled into the AMBE-2000™ ...
Page 22
... These four configurations can be seen in Table 4-B. See section 4.3 for all the details on the serial interface. DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Interface Select Pins Port Type ...
Page 23
... The signals in Table 4-C make up the serial channel interface. The serial channel mode transfers data in and out of the AMBE-2000™ using 16 bit words on the two data lines CHAN_RX_DATA and CHAN_TX_DATA. The selection of the framed or unframed format of this data is made using information in Table 4-A. ...
Page 24
... Table 4-D Switching Characteristics Over Recommended Operating Conditions for Serial Port Receive Reference Parameter t Hold time, FSR after CLKR falling edge h(FSR) t Hold time, DR after CLKR falling edge h(DR) DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 t c(SCK) t w(SCK) t w(SCK) t su(DR) t h(DR) MSB ...
Page 25
... Hold time, DX valid after CLKX rising edge h(DX) • Note 7.629 ns; however, do not operate serial clocks any faster than 2.048 MHz. Thus t minimum of 488.3 nsec. DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Min ...
Page 26
... Otherwise, when the data rate is less than 9600bps, the coded voice bits are filled starting from the MSB of the first word in the field, leaving any unused bits as zeros important to note here that even when the AMBE-2000™ is operating at less than 9600bps, all 384 bits of the Framed format (including any unused trailing zeros) must be transferred out of the encoder and into the decoder ...
Page 27
... Rate Info 0, Rate Info 1, Rate Info 2, Rate Info 3, Rate Info 4 The initial rate of the AMBE-2000™ is set through the hardware pins RATE_SEL [4-0] (see Section 7.2 and Tables 7-A and 7- B). After resetting the device, the coding rate can be modified for both the encoder and the decoder by sending a framed packet to the input channel interface ...
Page 28
... The AMBE-2000™ uses these five words to set the source and FEC coding rates. Tables 5-C and 5-D list predefined values for various source and FEC rates. These are only a representation of the most common rates that are requested. Please contact DVSI for additional rate information if the desired rates are not listed. The software configurations in Table 5-C are compatible for use with the AMBE-1000™ ...
Page 29
... Framed Input: Word 11 : Control Word 2 Table 5-G Control Word 2 Format Bit Decoder Output Volume Control DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 DTMF Control – 16-bits DTMF Digit Frequency 1 (Hz) ...
Page 30
... As is noted in the Channel Interface definitions, these unused bits must still be clocked out of the AMBE-2000™. The packet must always consist of 24 words. DVSI Confidential Proprietary, Subject to Change Visit us at www ...
Page 31
... Table 5-J Control Word 1 Format 7: MSB 6 Unused Unused DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Figure 5-B Basic Framed Output Description Header always set to 0x13ec Power Control ID (8bits) Control Word 1 (8 bits) – see Table 5-J Rate info 0 ...
Page 32
... This status field works in conjunction with the RIS bits in control word 2. Every time the RIS bits are set to any value other than 0x3, this field is reset. The number of bit errors is calculated only when using FEC provided by the AMBE-2000 DVSI Confidential Proprietary, Subject to Change Visit us at www ...
Page 33
... MSB DTMF Amplitude DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Description An input signal shall not be rejected as a DTMF tone if its amplitude is greater than -25 dBm0 (maximum sinusoid dBm0 is defined as+3.17 dBm0). In order for an input signal to correspond to a valid DTMF tone, the ratio of in-band to out-of- band energy must be greater than 15dB. In-band energy is defined to be the energy in frequency components within ± ...
Page 34
... Rate Information Selector (RIS): This field is used to indicate which part of the device is affected by words 2-6, the rate control words. Table 5-O Rate Information Selection Codes DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 DTMF Digit Frequency 1 (Hz) 1 ...
Page 35
... LSB of the final word. If the data rate selected is less than 9600bps then the unused bits in each frame are zero and populate the end of the field noted in the Channel Interface definitions, these unused bits must still be clocked out of the AMBE-2000™. The packet must always consist of 24 words. 5.4 ...
Page 36
... Word Format D 2 bits per Word Format D 3 bits per Word Format D 4 bits per Word Format D DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Data Control Offset ...
Page 37
... The AMBE-2000™ Vocoder Chip operates with a speech data sample rate of 8kHz for both the A/D and D/A interfaces. This 8kHz data is input and output using a serial port on the AMBE-2000™. ...
Page 38
... Table 6-B Switching Characteristics Over Recommended Operating Conditions for Serial Port Receive Reference Parameter t Hold time, FSR after CLKR falling edge h(FSR) t Hold time, DR after CLKR falling edge h(DR) DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 t c(SCK) t w(SCK h(FSR) w(SCK) t su(FSR) t ...
Page 39
... Hold time, DX valid after CLKX rising edge h(DX) • Note 7.629 ns; however, do not operate serial clocks any faster than 2.048 MHz. Thus t minimum of 488.3 nsec. DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Min ...
Page 40
... Coding Rate Selection The Voice coding rate as well as the FEC coding rate can be selected individually on the AMBE-2000™. These rates are selected by using the Rate Info Words as described in section 5.2.4, or through hardware pins RATE_SEL [4-0] subject to the restrictions in section 7.1. The five input pins RATE_SEL [4-0] give 32 pre-configured voice/FEC rates. If rates other than these are desired then the Rate Info Words (in the Framed channel interface) can be used to configure voice and FEC rates in 50 bps increments ...
Page 41
... Echo Cancellation The AMBE-2000™ Vocoder Chip provides a 16-millisecond echo canceller that is suitable for canceling the local echo caused by a 2-to-4 wire hybrid and can achieve echo cancellation of approximately 30dB or more. Only the linear portion of the echo is cancelled, so circuits should be designed to minimize non-linearities. ...
Page 42
... Normal Power and Power Saving Modes Power savings can be achieved during times of longer inactivity of the AMBE-2000™ chip by placing it into one of three available Low Power Modes. The chip can be placed into low-power and stand-by modes via hardware or software Control Words. In low power modes the A/D-D/A port will be disabled, concurrently halting any processing of voice frames in either direction. Depending on the low power state selected, either a Wake Up Control Word or a hardware reset on RESETN is necessary to return the AMBE-2000™ ...
Page 43
... Enter State via Normal Operation N/A SLEEP_EN pin at Standard Sleep reset OR Control Word Power Down Control Word DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com AMBE-2000™ Vocoder Chip User’s Manual Version 4.0 Return to Normal Wake Up Operation via Time N/A N/A Control Word N RESETN 95 ms ...
Page 44
... In any real time communication system, clock skew issues must be anticipated to keep the flow of data smooth from one end of the system to the other. The SLIP_EN (pin 82) signal allows the encoder of the AMBE-2000™ to react to small slips in the encoder channel signals. When the AMBE-2000™ active mode, the chip produces the signals internally for the transfer of data ...
Page 45
... Method 2 - Extended Slip Control with Periodic Slip Control Packets The AMBE-2000™ can provide extended slip compensation through the insertion of Slip Control Packets. One method of using this capability is for the system to periodically insert these Slip Control Packets into the data stream sent to the AMBE- 2000™ ...
Page 46
... The preferred method for using Slip Control Packets is to monitor the availability of data from the AMBE-2000™ vocoder chip and to only input Slip Control Packets into the data stream sent to the AMBE-2000™ as needed. Note that for this method slip control must be enabled (SLIP_EN is high) on the chip. This method provides compensation for the widest range of clock drift (1.2% or 12000 ppm), with the greatest flexibility in frame-interval and sample-rate timing. In this method the same Slip Control Packets shown in Table 7D are inserted into the data stream going to the AMBE-2000™ ...
Page 47
DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com Page 47 ...
Page 48
... CODEC_TX_DATA AMBE-2000 REFERENCE DATA The AMBE-2000™ sends the following configuration sequence to the AD73311 when CODEC_SEL [1-0]=01b: 0x8113, // write 13 to CRB of AD73311, MCD=1 (DMCLK=MCLK/2),SCD=0(SCLK=DMCLK/8) 0x82f9, // write f9 to CRC of AD73311, 5VEN, REFOUT, all Power ON 0x8300, // write 0 to CRD of AD73311 0x8001 // write 1 to CRA of AD73311 (Enters Data Mode) ...
Page 49
... BELOW Figure 1: AMBE-2000™ and TLV320AIC10 sample block diagram Configuration: To configure the AMBE-2000™ for operation with the TLV320AIC10, set the CODEC_SEL pins on the AMBE- 2000™ vocoder chip to work with a generic 16 bit linear 8 kHz codec as follows: CODEC_SEL [1-0] (pins 85,84) = 00b DVSI Confidential Proprietary, Subject to Change Visit us at www ...
Page 50
... TLV320AIC10 by writing data to its 4 control registers through the DCSI port, while the AMBE-2000™ is held in reset. The timing for the DCSI port is shown in Figure 2. Note that the Device Address (D14-D12) is normally set to 0 unless multiple codec devices are used in cascade. Be sure that the stop bit is at least 2 clock pulses long between data words as shown in the timing diagram ...
Page 51
Register Address Configuration Data (D11-D9) (D7-D0) 0x1 0x11 0x2 0x08 0x3 0x01 0x4 0x00 Table 1: Recommended TLV320AIC10 Configuration Data VDD CNTL_DATA [15:0] AIC_LOAD SCLK Figure 3: TLV320AIC10 Codec Configuration Detail DVSI Confidential Proprietary, Subject to Change Visit us at ...
Page 52
... Reference Materials: AMBE-2000™ Vocoder chips Users Manual: http://www.dvsinc.com/literature.htm TLV320AIC10 Data Sheet: http://www-s.ti.com/sc/ds/tlv320aic10.pdf TLV320AIC10 EVM User’s Guide: http://www-s.ti.com/sc/psheets/slwu003d/slwu003d.pdf Application Report – Understanding Data Converters: http://www-s.ti.com/sc/psheets/slaa013/slaa013.pdf DVSI Confidential Proprietary, Subject to Change Visit us at www ...
Page 53
TLV320AIC10 Reference Schematic (Analog Section) C1 820pF 3.3VA 10uF U1B R7 220 Handset DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com U1A ...
Page 54
... Configure the AMBE-2000™ for operation with the AD73311 Codec. Set the CODEC_SEL pins as shown. CODEC_SEL [1-0] (pins 85,84) = 01,b Hold the CODEC_TX_DATA lines on the AMBE-2000™ in tri-state (in the circuit set the SDI bit to 0,b) during power up. While the AMBE-2000™ lines are in tri-state, send the desired configuration words from the DSP/Microcontroller/logic to the AD73311 (Reset timing constraints for the AD73311 must be met) ...
Page 55
... The Analog Devices AD73311L is a low power 3 volt version of the AD73311 possible to use this part with the AMBE-2000™ or AMBE-2020™ vocoder chip utilizing the method described above for sending alternate configuration words to the AD73311 CODEC. Table 3 lists alternate control words for configuring the AD73311L for use with the AMBE-2000™ ...
Page 56
... Additional Reference Material AMBE-2000™ vocoder chip Users Manual http://www.dvsinc.com/literature.htm Application Report – Understanding Data Converters: http://www-s.ti.com/sc/psheets/slaa013/slaa013.pdf AD73311 - Data Sheet http://www.analog.com/productSelection/pdf/AD73311_b.pdf AD73311L - Data Sheet http://www.analog.com/productSelection/pdf/AD73311L_a.pdf DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com Page 56 ...
Page 57
... PCM3500 The block diagram in Figure 1 shows a sample interface between the PCM3500 codec and DVSI’s AMBE-2000™ vocoder chip. The AMBE-2000™ or AMBE-2020™ CODEC_SEL bits (see AMBE-2000™ or AMBE-2020™ users manual) must be set for use with a generic 16 bit linear codec (CODEC_SEL1,0 – 00). ...
Page 58
... CODEC_TX/RX_CLK 2 CODEC_TX/RX_STRB CODEC_TX_DATA 3.3VA CODEC_RX_DATA U1B - 3.3VA R8 10K + C13 10K 10uF R10 Figure 2 Page AMBE-2000™ and AMBE-2020™ Vocoder Chip Interface Applications Note 2.2uF 3.3 V Vcom Vcc C3 4.7uF 2 23 Vref1 AGND Analog Out ...
Page 59
... AMBE-2000™ or AMBE-2020™ vocoder chip Users Manual http://www.dvsinc.com/literature.htm Application Report – Understanding Data Converters: http://www-s.ti.com/sc/psheets/slaa013/slaa013.pdf PCM3500 Data Sheet http://www-s.ti.com/sc/ds/pcm3500.pdf PCM3500 Evaluation Board http://www-s.ti.com/sc/psheets/sbau028/sbau028.pdf AMBE-2000™ and AMBE-2020™ Vocoder Chip Interface Applications Note Page Jan 03 ...
Page 60
... Expanded Tone Detection and Generation The AMBE-2000™ is capable of detecting and generating single tones as well as dual tones. The single tones span from 156. 3812 31.25 Hz steps. Tone Index (Decimal) 0 ……… 122 123-127 128 …………. ...
Page 61
... Placing a logic high on pin 79 of either the AMBE-2000™ or AMBE-2020™ vocoder chips enables the soft decision error correction on the decoder. Enabling the soft-decision does nothing to the encoder packet. The packet will look like a normal encoded packet. The user must implement circuitry at the receive end of the channel for making a finer (4 bit) estimation of the received energy (see above link for an explanation of how this can be done). The AMBE-2000™ ...
Page 62
Table 1. Soft-Decision Decoder Packet Word # ...
Page 63
Revision Date of Number Revision 1.0 November 1999 1.1 April 2000 1.2 May 2000 Table 5-N Control Word Format: Removed VAD in bit 5. This is not 1.3 August 2000 1.4 October 2000 1.5 November 2000 2.0 January 2001 2.1 ...
Page 64
Revision Date of Number Revision 4.0 January 2003 DVSI Confidential Proprietary, Subject to Change Visit us at www.dvsinc.com History of Revisions Description Various Grammer Changes Vad Threshold Explination Associated Delay Front End Requirements Added AD73311AR Configuration Words Change to Echo ...