 |
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
| Datasheet File OCR Text: |
| HT8656 Talking Back Features * * * * * Operating voltage: 4.5V~5.5V ADM algorithm DRAM selection: - 64K - 256K Sampling rate selection: - 32Kb - 16Kb Auto stop recording - 0.5 seconds silence is detected - Recording capacity is full * * * * * * * Built-in 2-stage microphone amplifier Built-in DRAM refresh circuit Voltage type D/A output Current type D/A output Auto record and playback Auto power-off Low power consumption Applications * * Toys Education * Games General Description The HT8656 is a single chip CMOS LSI for talking back applications using an ADM algorithm. Functions of the IC consist of recording/playing as well as auto power off. It starts recording when a sound input is detected, and stops to play back when silence lasts 0.5 seconds during recording. The auto power off function is activated once a REC/PLAY cycle has been implemented 64 times or an interval of silence exceeds 2 minutes. The HT8656 provides a recording capacity of 2 seconds for DRAM of 64K and 8 seconds for DRAM of 256K at a 32Kb sampling rate and double recording capacity at a 16Kb sampling rate. A higher sampling rate will result in sounds of better quality but sacrifice the recording time, and vice versa. 1 5th May '98 HT8656 Pin Assignment Block Diagram 2 5th May '98 HT8656 Pad Coordinates Chip size: 3276.6 x 3530.6 (m)2 * The IC substrate should be connected to VDD in the PCB layout artwork. Unit: m Pad No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 X -1488.19 -1488.19 -1488.19 -1488.19 -1488.19 -1488.19 -1488.19 -1488.19 -1396.75 -1170.43 -964.69 -399.03 -145.29 1033.27 1239.01 Y 1613.92 1277.87 906.53 653.80 -355.60 -635.51 -937.26 -1378.46 -1615.19 -1615.19 -1615.19 -1615.19 -1615.19 -1615.19 -1615.19 Pad No. 16 17 18 10 20 21 22 23 24 25 26 27 28 29 X Y 1488.19 -1615.19 1488.19 -377.19 1488.19 -124.71 1488.19 130.30 1488.19 384.05 1488.19 651.51 1488.19 1089.41 1488.19 1363.73 1436.88 1615.19 1226.57 1615.19 973.84 1615.19 723.65 1615.19 473.20 1615.19 -1052.83 1615.19 3 5th May '98 HT8656 Pin Description Pin No. 1, 2 3~8 9 10 11 12 13 14 15 Pin Name I/O A6, A7 A5~A0 RASB WRB DATA A8 CASB OSC2 OSC1 O O O O I/O O O O I Internal Connection CMOS CMOS CMOS CMOS CMOS CMOS CMOS -- -- Description DRAM address output DRAM address output DRAM row address strobe DRAM write enable DRAM data input/output DRAM address output DRAM column address strobe Oscillator output Oscillator input 16 LEDB O LED indicator: NMOS Idle: LED is turned on Open Drain Record: LED flashes Play: LED is turned off NMOS System start pin Open Drain CMOS -- -- -- -- -- -- -- -- Pull-High Pull-High Motor drive output (active high) when playing back Negative power supply (GND) For internal AMP bias de-coupling Internal AMP first stage input (inverted) Internal AMP first stage output Internal AMP second stage input (inverted) Voltage type audio output for an external power AMP Current type audio output for an external transistor Positive power supply For IC test only 32Kbps/16Kbps sampling rate selection: Open/high: 32Kbps Low: 16Kbps 64K/256K DRAM size selection: Open/high: 64K Low: 256K 17 18 19 20 21 22 23 24 24 25 26 27 START MOTOR VSS BIAS AIN1 AO1 AIN2 IOUT (8656A) IOUT (8656B) VDD TESTB 16KB O O I I I O I O O I I I 28 MS I Pull-High 4 5th May '98 HT8656 Absolute Maximum Ratings* Supply Voltage ................................. -0.3V to 6V Input Voltage................. VSS-0.3V to VDD+0.3V Storage Temperature................. -50C to 125C Operating Temperature............... -20C to 70C *Note: These are stress ratings only. Stresses exceeding the range specified under "Absolute Maximum Ratings" may cause substantial damage to the device. Functional operation of this device at other conditions beyond those listed in the specification is not implied and prolonged exposure to extreme conditions may affect device reliability. Electrical Characteristics Symbol VDD IDD ISTB IO IOL IOL VIH VIL VOUT fOSC (Ta=25C) Parameter Operating Voltage Operating Current Standby Current Max. AUD Source Current MOTOR Source Current LED Sink Current "H" Input Voltage "L" Input Voltage Max. VOUT Output Voltage Oscillating Frequency Test Conditions VDD -- 5V 5V 5V 5V 5V -- -- 5V 5V Min. 4.5 -- -- -1.5 -1 3.0 0.7VDD 0 -- -- Typ. -- 1.5 600 -3.0 -3.5 5.0 -- -- 1.5 640 Max. 5.5 3.0 800 -- -- -- VDD 0.3VDD -- -- Unit V mA A Conditions -- No load, fOSC=640kHz -- VOH=0.6V VOH=4.5V VOL=0.5V -- -- RL>50k ROSC=43k mA mA mA V V VP-P kHz Functional Description The HT8656 is a single chip LSI with an external DRAM. It is designed for talking back applications. The recording length of the IC is determined by the data rate along with the size of an external memory. Sounds coming from an external microphone are coded through an internal ADM algorithm and saved in an external memory until the memory is full or an interval of silence lasts over 0.5 seconds. Once recording is terminated, the IC will play back the recorded sounds automatically. Record function The HT8656 provides two kinds of sampling rate and DRAM size selection to determine the recording capacity. The recording capacity is determined as shown on the following table. 5 5th May '98 HT8656 Sampling Rate (16KB) 32Kb 16Kb 32Kb 16Kb switched off when a REC/PLAY cycle has been implemented 64 times or an interval of silence lasts over 2 minutes. DRAM Type (MS) 64Kb 64Kb 256Kb 256Kb Recording Capacity 2 seconds 4 seconds 8 seconds 16 seconds Recording starts whenever a sound input is detected. It then stops once a 0.5 seconds silence is detected or the recording capacity is full. After that, talking back comes into play. Play function Motor The HT8656 stops to play back the recorded sounds when an interval of silence lasts 0.5 seconds during recording. Its sampling rate is the same as the rate of recording sounds. Power control The HT8656 provides a motor driving pin. The motor is turned on during playing but off once talking back is terminated. LED The HT8656 provides a START pin for power control. The START pin is of high impedance and switch Q is turned off initially. After the START pin is triggered, it will remain at a low level and switch Q is turned on. The START pin is of high impedance and the chip's power is The LED pin displays the status of the HT8656. LED is switched ON when the IC is in the standby state. Its intensity varies inversely with the sound volume when the IC is in the recording state. In the playing state, the LED is switched OFF. 6 5th May '98 HT8656 Flowchart 7 5th May '98 HT8656 Application Circuits LM386 output * Dice form * The IC substrate should be connected to VDD in the PCB layout artwork. 8 5th May '98 HT8656 * Package form 9 5th May '98 HT8656 two transistor output * Dice form * The IC substrate should be connected to VDD in the PCB layout artwork. 10 5th May '98 HT8656 * Package form 11 5th May '98 |
Price & Availability of HT8656
 |
|
|
|
|
All Rights Reserved © IC-ON-LINE 2003 - 2022 |
| [Add Bookmark] [Contact Us] [Link exchange] [Privacy policy] |
|
Mirror Sites : [www.datasheet.hk]
[www.maxim4u.com] [www.ic-on-line.cn]
[www.ic-on-line.com] [www.ic-on-line.net]
[www.alldatasheet.com.cn]
[www.gdcy.com]
[www.gdcy.net] |