SM8230A Tone Dialer with Built-in Piezo Driver OVERVIEW The SM8230A is a dual-tone signal generator LSI developed for DTMF (dual tone multi-frequency) dialing. It features a built-in piezo-electric speaker driver for direct connection to a piezo-electric buzzer. The DTMF frequencies can be set to correspond to the DTMF standards of any country. The output level is also adjustable under software control. These features, combined with its small package and low power dissipation, make the SM8230A a very use device to use. ■ ■ ■ ■ ■ 3-line serial interface to external CPU 2 independent, adjustable frequency outputs Piezo driver for direct connection to a piezo-electric buzzer 4 system clock frequencies selectable (480kHz, 960kHz, 1.92MHz, 3.84MHz) 2.6 to 3.3V supply voltage Low current consumption • 3.0mA (max) operating current • 1µA (max) standby current Package: 8-pin plastic SOP ORDERING INFORMATION Device Package SM8230AS 8-pin SOP (Top view) SD 1 8 VDD SCL BZH OE BZL VSS 4 CLK 5 PACKAGE DIMENSIONS (Unit: mm) Peripheral 4.4 ± 0.2 6.2 ± 0.3 ■ + 0.10 5.2 ± 0.3 1.27 0.4 ± 0.1 0.15 − 0.05 1.5 ± 0.1 ■ PINOUT 0.05 ± 0.05 FEATURES 0 to 10 0.4 ± 0.2 SEIKO NPC CORPORATION —1 SM8230A BLOCK DIAGRAM VDD Programmable Counter High Group ROM D/A Converter Output Control BZH Output Control BZL SD LATCH SELECTOR SCL OE CLK Programmable Counter Low Group VSS ROM D/A Converter PIN DESCRIPTION Number Name I/O Description 1 SD I Serial data input 2 SCL I Serial data transfer clock input. (For valid transfer, OE must stay LOW for 16 clock cycles.) 3 OE I DTMF output enable/serial data transfer select input. Serial data transfer is selected when LOW. 4 VSS – Ground 5 CLK I System clock input. The clock can be set to one of four frequencies (480kHz, 960kHz, 1.92MHz, 3.84MHz). 6 BZL O DTMF low-frequency group analog output 7 BZH O DTMF high-frequency group analog output 8 VDD – Supply voltage SEIKO NPC CORPORATION —2 SM8230A SPECIFICATIONS Absolute Maximum Ratings VSS = 0V Parameter Symbol Rating Unit Supply voltage range VDD −0.3 to 7.0 V Input voltage range VIN VSS − 0.3 to VDD + 0.3 V Output voltage range VOUT VSS − 0.3 to VDD + 0.3 V Storage temperature range Tstg −55 to 125 °C Power dissipation PD 250 mW Recommended Operating Conditions VSS = 0V Rating Parameter Symbol Condition Unit min typ max Supply voltage range VDD 2.6 3.0 3.3 V Operating temperature Topr −20 25 70 °C DC Characteristics VDD = 2.6 to 3.3V, VSS = 0V, Ta = −20 to 70°C Rating Parameter Symbol Condition Unit min typ max Operating current consumption IDD VDD = 3.0V, Ta = 25°C, fCLK = 480kHz – 1.5 3 mA Standby current consumption IST VDD = 3.3V, OE = LOW – – 1 µA VIH HIGH-level input 1.1 – VDD VIL LOW-level input VSS – 0.6 IIL HIGH/LOW-level input −1 – 1 µA 0.86VDD 0.93VDD 1.0VDD Vp-p – 1.0 – dB −1 – 1 dB 100 150 200 Ω Input voltage (all inputs) Input leakage current BZH/BZL tone output voltage VBZO BZH/BZL tone output adjustment step DRES BZH/BZL tone output absolute error DLIN BZH/BZL tone output impedance ZOUT 0dB output level VZBO levels V SEIKO NPC CORPORATION —3 SM8230A AC Characteristics VDD = 2.6 to 3.3V, VSS = 0V, Ta = −20 to 70°C Rating Parameter Symbol Condition Unit min typ max Tone output frequency error ∆f fCLK = 3.84MHz, no deviation – – 0.37 % Tone distortion1 DIS BZH/BZL – 5 10 % CLK cycle time tCLK 250 – – ns CLK LOW-level pulsewidth tCLKL 100 – – ns CLK HIGH-level pulsewidth tCLKH 100 – – ns OE setup time tSUOE 100 – – ns tHDOE 100 – – ns SCL cycle time tSCL 1 – – µs SCL LOW-level pulsewidth tSCLL 400 – – ns SCL HIGH-level pulsewidth tSCLH 400 – – ns Input data setup time tSUD 100 – – ns 100 – – ns OE hold time Input data hold time CLK input waveform Between OE and SCL SCL input waveform Between SD and SCL tHDD 1. Ta = −10 to 70°C, THD + N (10Hz to 500kHz), no load System clock input timing CLK tCLKL tCLKH tCLK Serial data transfer timing OE 1 SCL SD 2 DATA(b15) tSUD tSUOE tSCLH DATA(b14) 16 DATA(b0) tSCLL tHDD tSCL tHDOE SEIKO NPC CORPORATION —4 SM8230A FUNCTIONAL DESCRIPTION Serial Interface Data is transferred in 16-bit units by writing commands over a 3-line serial interface comprising OE (output enable), SCL (serial clock) and SD (serial data input). Note that data transfer is unidirectional; no data is output from the SM8230A. The operating sequence is described below. Port OE Serial Clock Serial Data CPU SCL SD (Clock) BZH R SM8230 Piezo Buzzer BZL CLK Figure 1. Serial interface connection example Command transfer Data can be transferred when OE goes LOW. Data is transferred in 16-bit units in sync with the rising edge of the SCL clock. Note that when OE is LOW and both SD and SCL are tied LOW, the current consumption is less than 1µA (standby mode). The internal states are undefined when power is first applied. DTMF analog signal output Data transfer stops and DTMF analog signal output starts when OE goes HIGH, as shown in figure 2. Piezo buzzer output Serial data transmission OE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 b8 b7 b6 b5 b4 b3 b2 b1 b0 SCL b15 b14 b13 b12 b11 b10 b9 SD 0 0 CK1 CK0 FH1 FH0 GH3 GH2 GH1 GH0 FL1 FL0 GL3 GL2 GL1 GL0 MSB LSB BZL Low frequency group output BZH High frequency group output Figure 2. Serial data transfer timing SEIKO NPC CORPORATION —5 SM8230A Transfer Command Specifications The transfer data code format is shown in figure 3. Data is transferred with the MSB as the leading bit. The data sets the input clock, high-frequency group and low-frequency group frequencies, and the output levels. The commands are shown in tables 1 to 4. b15 (MSB) 0 0 b0 (LSB) CK1 CK0 FH1 FH0 GH3 GH2 GH1 GH0 FL1 FL0 GL3 GL2 GL1 GL0 Low group output level set. Low group frequency set. High group output level set. High group frequency set. CLK pin input frequency set. Set (b14, b15) = (0, 0) for normal operation. Figure 3. Transfer command format CK command (CK1, CK0) These bits set the frequency of the input clock on CLK. The frequency can be set to 1×, 2×, 4×, and 8× multiples of 480kHz. The input code and the corresponding clock frequency are shown in table 1. Table 1. CK command CK1 CK0 CLK input clock frequency 0 0 480kHz 0 1 960kHz 1 0 1.92MHz 1 1 3.84MHz FH/FL command (HF1, FH0/FL1, FL0) These bits set the DTMF signal high-frequency and low-frequency group frequencies, respectively.The input code, the corresponding group frequency specification, the design value and frequency deviation are shown in tables 2 and 3. Note that the design value and frequency deviation are calculated values assuming a deviationfree system clock input on CLK. Table 2. FH command FH1 FH0 DTMF frequency [Hz] Design value [Hz] Deviation [%] 0 0 1209 1212.1 +0.26 0 1 1336 1333.3 −0.20 1 0 1477 1481.5 +0.30 1 1 1633 1632.7 −0.02 FH1 FH0 DTMF frequency [Hz] Design value [Hz] Deviation [%] 0 0 697 697.7 +0.10 0 1 770 769.2 −0.10 1 0 852 851.1 −0.11 1 1 941 937.5 −0.37 Table 3. FL command SEIKO NPC CORPORATION —6 SM8230A GH/GL command (GH3 to GH0, GL3 to GL0) These bits set the output levels of the high-frequency group and low-frequency group outputs, respectively. The input code and the corresponding output level are shown in table 4. Note that the 0dB point is typically 93% of the supply voltage. Any value above 0dB results in amplitude clipping of the output waveform. Table 4. GH/GL command GH3/GL3 GH2/GL2 GH1/GL1 GH0/GL0 Output level 0 0 0 0 −9dB 0 0 0 1 −8dB 0 0 1 0 −7dB 0 0 1 1 −6dB 0 1 0 0 −5dB 0 1 0 1 −4dB 0 1 1 0 −3dB 0 1 1 1 −2dB 1 0 0 0 −1dB 1 0 0 1 0dB 1 0 1 0 1dB 1 0 1 1 2dB 1 1 0 0 3dB 1 1 0 1 4dB 1 1 1 0 5dB 1 1 1 1 6dB SEIKO NPC CORPORATION —7 SM8230A Please pay your attention to the following points at time of using the products shown in this document. The products shown in this document (hereinafter “Products”) are not intended to be used for the apparatus that exerts harmful influence on human lives due to the defects, failure or malfunction of the Products. Customers are requested to obtain prior written agreement for such use from SEIKO NPC CORPORATION (hereinafter “NPC”). Customers shall be solely responsible for, and indemnify and hold NPC free and harmless from, any and all claims, damages, losses, expenses or lawsuits, due to such use without such agreement. NPC reserves the right to change the specifications of the Products in order to improve the characteristic or reliability thereof. NPC makes no claim or warranty that the contents described in this document dose not infringe any intellectual property right or other similar right owned by third parties. Therefore, NPC shall not be responsible for such problems, even if the use is in accordance with the descriptions provided in this document. Any descriptions including applications, circuits, and the parameters of the Products in this document are for reference to use the Products, and shall not be guaranteed free from defect, inapplicability to the design for the mass-production products without further testing or modification. Customers are requested not to export or re-export, directly or indirectly, the Products to any country or any entity not in compliance with or in violation of the national export administration laws, treaties, orders and regulations. Customers are requested appropriately take steps to obtain required permissions or approvals from appropriate government agencies. SEIKO NPC CORPORATION 15-6, Nihombashi-kabutocho, Chuo-ku, Tokyo 103-0026, Japan Telephone: +81-3-6667-6601 Facsimile: +81-3-6667-6611 http://www.npc.co.jp/ Email: [email protected] NC9614CE 2006.04 SEIKO NPC CORPORATION —8