SM6801A Class-D Mono Amplifier for Portable Device OVERVIEW The SM6801A is an analog-input, class-D mono amplifier. Class-D operation provides high efficiency and low power consumption. The device also incorporates an original real-time operation dynamic range compression function that effectively suppresses the distortion in the saturation level region output by soft-clipping, boosting the average sound pressure from the speaker during playback. It also incorporates an input equalizer pin for output speaker frequency characteristics adjustment. These features make the device ideal for use in mobile telephones and speaker applications requiring miniaturization and high-efficiency. The output stage has a BTL output configuration where the output waveform inverts only the modulation components, enabling direct drive connection, without using an LC filter, to a dynamic speaker. The device is available in miniature 16-pin QFN packages, and requires only a peripheral chip capacitor to form a miniature amplifier circuit. ■ ■ ■ ■ ■ ■ Operating supply voltage • VDDS = 2.0 to 3.6V (input, logic) • VDDP = 2.0 to 5.5V (output) Low current consumption: 4.2mA (VDD = 3.6V) 1.6mA (VDD = 2.4V) Output power: 0.7W (VDD = 3.6V, 8Ω load) 0.28W (VDD = 2.4V, 8Ω load) Output fundamental frequency: 125kHz Gain • 6dB (Normal) • 15dB to 6dB automatic adjustment in response to the input level (Dynamic range compression mode) Silicon-gate CMOS process Package: 16-pin QFN (Top view) OUTP VSS2 OUTN VDD3 ■ PINOUT VDD4 PDWN VDD2 MUTEN TESTN VSS1 EQN EQP DRCN VDD1 VREF1 IN FEATURES PACKAGE DIMENSIONS APPLICATIONS ■ ■ ■ (Unit: mm) Cellular phone PDA Digital still camera TOP VIEW 3.0 ± 0.08 BOTTOM VIEW 1.8 Device 1.8 0.3 ± 0.1 Package C 0.3 0.22 ± 0.05 φ 0.05 M S A B 0.2 S 0.05 S 0.5 0.7 ± 0.05 S 0.2 ± 0.05 16-pin QFN 0.1 ± 0.05 0.02 S A B SM6801AB 0.5 3.0 ± 0.08 ORDERING INFORMATION A 3 = 1.5 ± 0.05 B SEIKO NPC CORPORATION —1 SM6801A BLOCK DIAGRAM EQP EQN TESTN DRCN MUTEN PDWN VDD4 − IN LEVEL SHIFTER + BUFFER PWM Modulator VSS2 LEVEL SHIFTER − OUTP BUFFER OUTN + BIAS VREF VREF1 MUTE, POWER DOWN, PROTECTION OSC VSS1 VDD1 VDD2 VDD3 PIN DESCRIPTION Number Name*1 I/O*2 1 DRCN I Dynamic range compression mode setting (HIGH: normal operation, LOW: DRC mode) 2 VDD1 – Supply (input system) 3 VREF1 – Reference voltage 1 (bias voltage) 4 IN I Signal input 5 EQP I Equalizer network connection 6 EQN I Equalizer network connection 7 VSS1 – Ground (input system) 8 TESTN Ip Test pin (HIGH: normal operation, LOW: test mode) 9 VDD3 I Supply (OUTN stage) 10 OUTN O Speaker minus (–) output 11 VSS2 – Ground (output stage) 12 OUTP O Speaker plus (+) output 13 VDD4 – Supply (OUTP stage) 14 PDWN I Power-down control (active LOW) 15 VDD2 – Supply (logic system) 16 MUTEN I Mute control (active LOW) Function *1. VDDS = VDD1, VDD2, VDDP = VDD3, VDD4, VSS = VSS1, VSS2 *2. Ip = input pin with built-in pull-up resistor SEIKO NPC CORPORATION —2 SM6801A SPECIFICATIONS Absolute Maximum Ratings Parameter Symbol Rating Unit VDDS −0.3 to 4.6 V VDDP −0.3 to 7.0 V VSS 0 V VIN VSS − 0.3 to VDDS + 0.3 V TSTG −55 to 125 °C IO 300 mA PD 1280 (Ta = 25°C)*1 mW Supply voltage range Input voltage range Storage temperature range Output current Power dissipation *1. When mounted on a 3.5cm × 3.5cm board, the power dissipation is related to the operating temperature by the following equation. ■ ■ ■ Maximum junction temperature: TMAX = 125°C Operating ambient temperature: Ta = [°C] Thermal resistance: θJ = 78.0°C/W PD = (TMAX − Ta) θJ 1.4 1.28 Power dissipation [W] 1.2 1.02 1 0.76 0.8 0.51 0.6 0.4 0.2 0 25 35 45 55 65 75 85 Operating temperature [°C] Recommended Operating Conditions VSS = VSS1 = VSS2 = 0V, VDDS = VDD1 = VDD2, VDDP = VDD3 = VDD4 unless otherwise noted. Parameter Symbol Rating Unit Supply voltage 1 VDDS 2.0 to 3.6 V Supply voltage 2 VDDP 2.0 to 5.5 V VDD3 − VDD4 ± 0.1 V Ta −40 to 85 °C Supply voltage difference Operating ambient temperature Note. VDDP ≥ VDDS VDDS and VDDP should be applied simultaneously. SEIKO NPC CORPORATION —3 SM6801A Electrical Characteristics DC Characteristics Standard voltage VSS1 = VSS2 = 0V, VDD1 = VDD2 = 2.7 to 3.6V, VDD3 = VDD4 = 2.7 to 5.5V, Ta = −40 to 85°C unless otherwise noted. Rating Parameter Pin VDD1 Current consumption Symbol Conditions Unit min typ max IDD1A (Note 1) – 3.8 6.0 mA IDD1S (Note 2) – 0.1 0.5 µA VDD3 = VDD4 = 3.6V – 0.3 1.5 mA IDDAA (Note 1) VDD3 = VDD4 = 5V – 1.0 6.0 mA VDD3 = VDD4 = 3.6V – 0.1 0.3 µA IDDAS (Note 2) VDD3 = VDD4 = 5V – 0.1 0.3 µA VIH1 HIGH level 0.7VDD1 – – V VIL1 LOW level – – 0.3VDD1 V VIH2 HIGH level 1.6 – – V VIL2 LOW level – – 0.4 V IIL1 VIN = VSS − – 90 µA ILH1 VIN = VDDS − − 1.0 µA VDD2 Input voltage 1 Input voltage 2 Input current 1 Input current 2 TESTN, DRCN MUTEN, PDWN TESTN, DRCN, MUTEN, PDWN Note 1. MUTEN = HIGH, PDWN = HIGH, input and VREF1 connected by 600Ω, DRCN = HIGH, no-load output Note 2. MUTEN = LOW, PDWN = LOW, input and VREF1 connected by 600Ω, DRCN = HIGH, no-load output Low voltage VSS1 = VSS2 = 0V, VDD1 = VDD2 = VDD3 = VDD4 = 2.0 to 3.2V, Ta = −40 to 85°C unless otherwise noted. Rating Parameter Pin VDD1 Current consumption VDD2 Input voltage 1 Input voltage 2 Input current 1 Input current 2 TESTN, DRCN MUTEN, PDWN TESTN, DRCN, MUTEN, PDWN Symbol Conditions Unit min typ max IDD1A (Note 1) – 1.6 6.0 mA IDD1S (Note 2) – 0.1 0.5 µA IDDAA (Note 1) – 0.2 1.5 mA IDDAS (Note 2) – 0.1 0.3 µA VIH1 HIGH level 0.7VDD1 – – V VIL1 LOW level – – 0.3VDD1 V VIH2 HIGH level 1.6 – – V VIL2 LOW level – – 0.4 V IIL1 VIN = VSS − – 90 µA ILH1 VIN = VDDS − − 1.0 µA Note 1. MUTEN = HIGH, PDWN = HIGH, input and VREF1 connected by 600Ω, DRCN = HIGH, no-load output Note 2. MUTEN = LOW, PDWN = LOW, input and VREF1 connected by 600Ω, DRCN = HIGH, no-load output Note. The usage with direct coupling to load is recommended for operating VDD1, VDD2, VDD3 and VDD4 at ≤ 2.4V. When using LC-type LPF, the ringing phenomena due to rush current may be judged as short-circuit of the load. In this case, the normal operation will start after the mute for 5 seconds. SEIKO NPC CORPORATION —4 SM6801A AC Analog Characteristics VDD1 = VDD2 = VDD3 = VDD4 = 3.6V, VSS1 = VSS2 = 0V, 0.708Vrms analog input amplitude, 1kHz input signal frequency, Ta = 25°C, "Measurement Block Diagram", "Measurement Conditions", "Measurement Circuit", DRCN = PDWN = MUTEN = HIGH, unless otherwise noted. Analog Input Characteristics (IN) Standard voltage: VDD1 = VDD2 = VDD3 = VDD4 = 3.6V, VSS1 = VSS2 = 0V Rating Parameter Symbol Conditions Unit min typ max Reference input amplitude 1 VAI1 PO = 0.25W – 0.708 – Vrms Reference input amplitude 2 VAI2 PO = 0.05W – 0.178 – Vrms Input resistance RIN 40 60 80 kΩ Input clipping voltage VCLP 0.7 1 1.3 Vrms PO = 0.5W Low voltage: VDD1 = VDD2 = VDD3 = VDD4 = 2.4V, VSS1 = VSS2 = 0V Rating Parameter Symbol Conditions Unit min typ max Reference input amplitude 1 VAI1 PO = 42mW – 0.316 – Vrms Reference input amplitude 2 VAI2 PO = 8mW – 0.045 – Vrms Input resistance RIN 40 60 80 kΩ Input clipping voltage VCLP 0.38 0.48 0.58 Vrms PO = 100mW SEIKO NPC CORPORATION —5 SM6801A Analog Output Characteristics (OUTP, OUTN) Standard voltage: VDD1 = VDD2 = VDD3 = VDD4 = 3.6V, VSS1 = VSS2 = 0V Rating Parameter Symbol Conditions Unit min typ max Voltage gain 1 A1 DRCN = HIGH, input amplitude = 0.1Vrms 4.0 6.0 8.0 dB Voltage gain 2 A2 DRCN = LOW, input amplitude = 0.05Vrms 13.0 15.0 17.0 dB Residual noise voltage VNS DRCN = HIGH, input and VREF1 connected by 600Ω – 78 120 µVrms PO = 0.25W, reference input amplitude 1 – 0.4 1.0 % 0.6 0.7 0.8 W –90.0 –110 – dBV Total harmonic distortion + noise THD + N Maximum output power POMAX Output power when THD = 10% Mute-mode output voltage VMUTE Output power when MUTEN = LOW HIGH-level output voltage VOH VDDP – 0.2 VDDP – 0.02 VDDP + 0.2 V LOW-level output voltage VOL 0 0.02 0.2 V Efficiency EEF Maximum output power conditions 80 83 – % (Note 1) – –60 – dB Ripple rejection ratio 1 PSRR1 Note 1. DRCN = HIGH, 217Hz ripple frequency, 0.2Vrms ripple amplitude on VDD1/VDD2/VDD3/VDD4, input and VREF1 connected by 600Ω. Low voltage: VDD1 = VDD2 = VDD3 = VDD4 = 2.4V, VSS1 = VSS2 = 0V Rating Parameter Symbol Conditions Unit min typ max Voltage gain 1 A1 DRCN = HIGH, input amplitude = 0.1Vrms – 5.6 – dB Voltage gain 2 A2 DRCN = LOW, input amplitude = 0.05Vrms – 14.5 – dB Residual noise voltage VNS DRCN = HIGH, input and VREF1 connected by 600Ω – 120 – µVrms THD + N PO = 42mW, reference input amplitude V = 316.2mVrms – 0.8 – % Total harmonic distortion + noise Maximum output power POMAX Output power when THD = 10% – 0.280 – W Mute-mode output voltage VMUTE Output power when MUTEN = LOW – –110 – dBV HIGH-level output voltage VOH – VDDP – 0.02 – V LOW-level output voltage VOL – 0.02 – V SEIKO NPC CORPORATION —6 SM6801A Reference Voltage Characteristics (VREF1) Rating Parameter Symbol Reference output voltage 1 VREF1 Unit min typ max 0.45VDDS 0.5VDDS 0.55VDDS V Measurement Block Diagram 40µH BALANCED INPUT + SPOUT POS 1µF EVALUATION BOARD 8Ω AUDIO ANALYZER 40µH BALANCED INPUT − SPOUT NEG 1µF Measurement Conditions Parameter Audio Analyzer (Audio Precision System Two Cascade) Built-in Filters Excluding residual noise Low-pass filter (20kHz) ON High-pass filter (22Hz) ON Residual noise voltage Low-pass filter (20kHz) ON High-pass filter (22Hz) ON A-weighted SEIKO NPC CORPORATION —7 SM6801A Measurement Circuit DRCN MUTEN VDD2 PDWN SW2* H SW3* L SW4* H H L L VDD4 PDWN VDD2 MUTEN POWER VDD C6 1µ R5* VDD1 DRCN OUTP VDD1 VSS2 SPOUT POS POWER VSS (0V) R6* IN EQN 1µ TESTN C7 VSS1 1µ EQP IN SIGNAL INPUT C5 SPOUT NEG OUTN VREF1 C1 1µ VDD3 C4 150p SW1* H L EQP EQN VSS1 ANALOG VSS (0V) TESTN SIGNAL VSS (0V) Note. *C2, C3: not inserted *R1, R2, R3, R4: not inserted *R5, R6: series resistors for dielectric speaker *SW1: HIGH = Normal, LOW = Test *SW2: LOW = DRC on, HIGH = DRC off *SW3: LOW = Mute on, HIGH = Mute off *SW4: LOW = Power off, HIGH = Power on SEIKO NPC CORPORATION —8 SM6801A FUNCTIONAL DESCRIPTION Power-down (PDWN) The device enters power-down mode when PDWN goes LOW. When powered-down, the outputs become high impedance and the internal oscillation stops. In power-down mode, the MUTEN pin should be held LOW. Mute (MUTEN) Mute operation occurs when MUTEN goes LOW. In mute mode, the outputs become high impedance. During mute operation, the protection circuit operation is disabled, but the outputs are protected against output short circuits by their high impedance state. When power is applied, MUTEN should be held LOW for a short interval, shown in the timing diagram below, to prevent pop noise from the speaker. Also, applying and releasing mute operation after power is applied can occur at high speed without generating pop noise. min. 40msec PDWN MUTEN Note. VREF1 load capacitance = 1µF Protection Circuit The protection circuit operates if there is an output short-circuit to the supply, short-circuit to ground, or other excessive load abnormal condition lasting longer than approximately 1µs. Normal operation resumes after approximately 5 seconds. When the protection circuit becomes active, the outputs become high impedance. The usage with direct coupling to load is recommended for operating VDD1, VDD2, VDD3 and VDD4 at ≤ 2.4V. When using LC-type LPF, the ringing phenomena due to rush current may be judged as short-circuit of the load. In this case, the normal operation will start after the mute for 5 seconds. SEIKO NPC CORPORATION —9 SM6801A Input Equalizer (IN, EQP, EQN) An input equalizer network can be connected to pins IN, EQP and EQN, as shown in the input equivalent circuit and equalizer circuit below. R01 R04 R02 C02 R03 C03 C04 EQP 5 EQN 6 60k IN' 60k C01 4 − IN + VREF1 The frequency response of the equalizer circuit is given by the following equation, where ƒ is the frequency. 1 1 + 60000 1 1 R03 + 2πƒC03 Response = 20 × log10 1 + 2πƒC01 + 1 + 2πƒC04 R04 [dB] 1 1 1 + + 60000 R01 1 R02 + 1 2πƒC02 Dynamic Range Compression Mode (DRCN) The dynamic range compression mode is set when DRCN is LOW. When a compression mode is used, the gain for small input signals is increased while large input signals are converted using a curve that performs soft-clipping. This increases the average sound pressure level emitted from the speaker during playback. -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 10 5 0 DRC mode Output [dBV] -5 -10 -15 -20 normal mode -25 -30 -35 -40 Input [dBV] SEIKO NPC CORPORATION —10 SM6801A TYPICAL APPLICATION CIRCUITS Dynamic Speaker LC-type LPF Connection 47µF OUTPUT IN SPOUT POS 1µF SOUND GENERATOR IC SM6801 47µF SPOUT NEG 1µF Direct Connection OUTPUT IN SOUND GENERATOR IC SPOUT POS SM6801 SPOUT NEG Dielectric Speaker A dielectric speaker is capacitive in nature, and therefore requires output resistor connection. OUTPUT SOUND GENERATOR IC IN 4Ω SPOUT POS * SM6801 4Ω SPOUT NEG * Dielectric speaker Taiyo Yuden MLS20070, MLS23070, MLS25070 or similar SEIKO NPC CORPORATION —11 SM6801A Mounting Circuits Connection to LC Filter VDD3 + Ferrite beads VDD2 VSS2 + VCC 1µF 1µF VDD4 VCC Ferrite beads VDD1 1µF SM6801 VSS1 Z0 VSS OUTP Ferrite beads LC filter OUTN Ferrite beads LC filter Speaker Direct Connection to Load VDD3 Ferrite beads + VDD2 VSS2 + VCC VCC 10µF 10µF VDD4 Ferrite beads OUTP Ferrite beads OUTN Ferrite beads VDD1 1µF SM6801 VSS1 Z0 VSS Speaker Note. As for the wiring to VDD1, VDD2, VDD3, VDD4, VSS1, and VSS2, we recommend to wire from the power supply block. The recommended value of internal impedance (Z0) is approximately less than 1/40 of load resistance. SEIKO NPC CORPORATION —12 SM6801A TYPICAL CHARACTERISTICS Measurement conditions: Refer to “Analog Output Characteristics”. Measurement circuit: Refer to “Measurement Circuit”. +10 +5.833 +1.667 DRC -2.5 Output [dBV] -6.667 -10.833 -15 NORMAL -19.167 -23.333 -27.5 -31.667 -35.833 -40 -40 -35 -30 -25 -20 -15 -10 -5 +0 +5 Input [dBV] Input vs. Output 1.8 1.2 0.9 0.6 0.3 0 2.5 3 3.5 4 4.5 5 5.5 Supply voltage [V] Supply voltage vs. Output power 100 10 50 5 10 THD + N 5 1 Output power 500m 2 200m 1 100m 0.5 50m 0.2 20m 0.1 10m 0.05 5m 2m 0.02 0.01 -25 Output power [W] 2 20 THD + N [%] Output power [W] 1.5 1m -22.5 -20 -17.5 -15 -12.5 -10 -7.5 -5 -2.5 +0 +2.5 +5 Input [dBV] Input vs. THD + N and output power SEIKO NPC CORPORATION —13 SM6801A 10 5 VDD3 = VDD4 = 5.5V 2 1 VDD3 = VDD4 = 5V Output power [W] 500m 200m 100m 50m 20m 10m VDD3 = VDD4 = 4.5V 5m 2m 1m -25 -22.5 -20 -17.5 -15 -12.5 -10 -7.5 -5 -2.5 +0 Input [dBV] Input power vs. Output power -70 -75 -80 -85 -90 Noise [dB] -95 -100 -105 -110 -115 -120 -125 -130 -135 -140 20 50 100 200 500 1k 2k 5k 10k 20k Frequency [Hz] Residual noise vs. Frequency 10 5 +6 +5 1 +3 0.5 +2 0.2 0.1 +1 -0 0.05 -1 -2 0.02 0.01 Output Output [dBr] THD + N [%] +4 THD + N 2 -3 0.005 -4 -5 0.002 0.001 20 -6 50 100 200 500 1k 2k 5k 10k 20k Frequency [Hz] THD + N and output voltage vs. Frequency +0 -10 -20 PSRR [dBr] -30 PSRR -40 -50 -60 -70 -80 -90 -100 10 20 50 100 200 500 1k 2k 5k 10k 20k Frequency [Hz] PSRR vs. Frequency SEIKO NPC CORPORATION —14 SM6801A FOOTPRINT PATTERN 3.6 ± 0.1 2.2 ± 0.1 0. 32 0.25 ± 0.05 0.7 ± 0.1 2.2 ± 0.1 0.5 × 3 = 1.5 ± 0.05 3.6 ± 0.1 0.5 × 3 = 1.5 ± 0.05 SEIKO NPC CORPORATION —15 SM6801A 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] NC0416DE 2007.06 SEIKO NPC CORPORATION —16