IS31AP2145A 2.9W@5V MONO CLIP-LESS & FILTER-LESS CLASS-D AUDIO POWER AMPLIFIER DESCRIPTION RECOMMENDED EQUIPMENT The IS31AP2145A is a [email protected] mono, clip-less, filter-less, high efficiency Class-D audio power amplifier with automatic gain control. The IS31AP2145A integrates an AGC (Automatic Gain Control) function to automatically prevent distortion of the audio signal by which we can enhance audio quality and also protect the speaker from damage at high power levels. The AGC function and its attack time/release time are selectable via the CTRL pin. The IS31AP2145A also provides thermal and over current protection functions. The demo board has four modes (AGC1, AGC2, AGC OFF, and SHUTDOWN) to test the functionality of the IS31AP2145A. FEATURES Operating from VCC = 2.7V ~ 5.5V Filter-less Class-D architecture AGC enable/disable function 2.7W into 4Ω at 5.0V (10% THD+N) Minimum external components High efficiency: 90% Click-and-pop suppression Short-circuit and thermal protection Space-saving UTQFN-9, 1.5mm × 1.5mm 5.0V, 2A power supply Audio source (i.e. MP3 player, Notebook PC, etc.) 8Ω or 4Ω speakers ABSOLUTE MAXIMUM RATINGS ≤ 5.5V power supply Caution: Do not exceed the conditions listed above, otherwise the board will be damaged. PROCEDURE The IS31AP2145A demo board is fully assembled and tested. Follow the steps below to verify board operation. Caution: Do not turn on the power supply until all connections are completed. 1) 2) 3) QUICK START 4) Connect a 4Ω (or larger) speaker across the OUTterminal and OUT+ terminal or the RCA female connector (SPK CON3). Connect the ground terminal of the power supply to the GND (TP2) and the positive terminal to the VCC (TP1). Or connect DC power to connector (DC IN) with a 2.5 mm jack. If the audio source is differential, remove jumper JP1, connect the negative of the audio source to the IN- terminal, and connect the positive of the audio source to IN+ terminal. If the audio source is single-ended, connect the audio source to the IN+ terminal, and close jumper JP1; or connect audio source to the audio mono connector (AUDIO IN) and close jumper JP1. Turn on the power supply, and pay attention to the supply current. If it is over 1.5A, turn off power and check the evaluation board for short circuit connections. Figure 1: Photo of IS31AP2145A Evaluation Board ORDERING INFORMATION Part No. Temperature Range Package IS31AP2145A-UTLS2-EB -40°C ~ +85°C (Industrial) UTQFN-9, Lead-free Table 1: Ordering Information For pricing, delivery, and ordering information, please contact ISSI’s analog marketing team at [email protected] or (408) 969-6600. Integrated Silicon Solution, Inc. – www.issi.com Rev. A, 01/13/2015 1 IS31AP2145A 2.9W@5V MONO CLIP-LESS & FILTER-LESS CLASS-D AUDIO POWER AMPLIFIER EVALUATION BOARD OPERATION HIGH-PASS FILTER The IS31AP2145A demo board has an LPC922 MCU to read the status of the four buttons which select between the different modes shown in Table Co1 below. The current operating mode is indicated by the illuminated LED above the appropriate button. The default mode is AGC1 enabled. The evaluation board’s high-pass filter consists of the input capacitors CIN (C4 or C5) and RIN (IS31AP2145A internal resistance (28.5kΩ) + (R1 or R2). The filter’s corner frequency, fC, is determined by Equation (1). 1 f c 2R C IN IN Table 2 Mode settings The corner frequency can be adjusted by replacing the R1 or R2 0Ω resistors with a larger resistor value or by increasing/decreasing the C4 or C5 capacitance. CTRL1 CTRL2 Mode H H AGC1 H GND AGC2 GND H AGC OFF GND GND Shutdown See the IS31AP2145A configuration details. datasheet (1) for SHUTDOWN MODE The SHUTDOWN button selects the power-down mode of the IS31AP2145A. mode Note: The IS31AP2145A Mode setting is controlled by the onboard LPC922 MCU. TP1 C2 1uF C3 0.1uF 10nF R1 0R A1 IN+ B2 TP4 10nF R2 OUT+ 0R C1 SPK C11 SHUTDOWN K4 3 20 8 9 10 5 P0.4 P1.7 P0.5 P0.0 VDD P0.1 P0.6 INT1/P1.4 T1/P0.7 INT0/P1.3 T0/P1.2 TXD/P1.0 GND RXD/P1.1 GND 18 R11 1K D2 17 3V U2 C8 1uF C9 16 0.1uF 15 14 R12 1K D3 13 R13 1K D4 12 11 VCC C7 10nF 4 D1 BP P1.6 1K EN P0.3 R10 GND 2 OSC1 3V 19 Vdd Vout 1 P0.2 4 3 AGC OFF K3 6 OSC2 IS31AP2145A 1 AGC2 K2 7 Speaker TP6 VCC RST R6 R7 R8 R9 10K 10K 10K 10K C3 OUT- 0.1uF U3 3V AGC1 CTRL 33K R4 R5 22K K1 C2 SD GND 68K B3 CTRL2 R3 OUT- B1 CTRL1 CLOSE=SE CON3 IN- TP7 JP1 TP5 A3 OUT+ 2 C5 IN+ U1 VREF C4 1uF VDD TP2 IN- C10 A2 C1 10uF TP3 CON2 AUDIO IN VCC VCC 5 CON1 DC IN PAM3101 C6 1uF CTRL2 CTRL1 LPC922 Figure 2: IS31AP2145A Application Schematic Integrated Silicon Solution, Inc. – www.issi.com Rev. A, 01/13/2015 2 IS31AP2145A 2.9W@5V MONO CLIP-LESS & FILTER-LESS CLASS-D AUDIO POWER AMPLIFIER BILL OF MATERIALS Name Symbol Amplifier U1 LDO Description Qty Supplier Part No. Class-D audio amplifier 1 ISSI IS31AP2145A-UTLS2 U2 Low-dropout regulator 1 PAM PAM3101 MCU U3 Microcontroller 1 NXP LPC922 LED D1~D4 LEDs Blue, SMD 4 Everlight 19-217/BHC-ZL1M2RY/3T Resistor R1, R2 RES,0R,1/16W,±5%,SMD 2 Yageo RL0603FR-0700KL Resistor R3 RES,68K,1/16W,±1%,SMD 1 Yageo RC0603FR-0768KL Resistor R4 RES,33K,1/16W,±1%,SMD 1 Yageo RC0603FR-0733KL Resistor R5 RES,22K,1/16W,±1%,SMD 1 Yageo RC0603FR-0722KL Resistor R6~R9 RES,10K,1/16W,±5%,SMD 4 Yageo RC0603JR-0710KL Resistor R10~R13 RES,1K,1/16W,±5%,SMD 4 Yageo RC0603JR-071KL Capacitor C1 CAP,10µF,10V,±10%,SMD 1 Yageo CC0805KRX7R6BB106 Capacitor C2, C10 CAP,1µF,50V,±10%,SMD 2 Yageo CC0603KRX7R9BB105 Capacitor C3, C9,C11 CAP,0.1µF,50V,±10%,SMD 3 Yageo CC0603KRX7R9BB104 Capacitor C4, C5, C7 CAP,10nF,50V,±10%,SMD 3 Yageo CC0603KRX7R9BB103 Capacitor C6, C8 CAP,1µF,25V,±10%,SMD 2 Yageo CC0805KRX7R8BB105 Button K1~K4 Button SMD 4 Connector DC IN 2.5mm DC connector 1 Connector SPK RCA type plugs 1 Connector AUDIO IN 3.5mm min plug 1 TP1~TP7 TP1~TP7 Test pins 7 Bill of materials refers to Figure 2 above. Integrated Silicon Solution, Inc. – www.issi.com Rev. A, 01/13/2015 3 IS31AP2145A 2.9W@5V MONO CLIP-LESS & FILTER-LESS CLASS-D AUDIO POWER AMPLIFIER 0 0 2 1 2 2 1 2 1 2 2 1 2 1 2 1 2 1 2 2 2 1 0 0 Figure 3: Board Component Placement Guide - Top Layer Figure 4: Board PCB Layout - Top Layer Integrated Silicon Solution, Inc. – www.issi.com Rev. A, 01/13/2015 4 IS31AP2145A 2.9W@5V MONO CLIP-LESS & FILTER-LESS CLASS-D AUDIO POWER AMPLIFIER 0 0 2 2 1 0 0 0 0 1 0 0 2 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 2 1 0 0 0 0 1 0 0 0 0 0 2 1 2 1 0 1 2 2 2 1 0 0 Figure 5: Board Component Placement Guide - Bottom Layer Figure 6: Board PCB Layout - Bottom Layer Copyright © 2015 Integrated Silicon Solution, Inc. All rights reserved. ISSI reserves the right to make changes to this specification and its products at any time without notice. ISSI assumes no liability arising out of the application or use of any information, products or services described herein. Customers are advised to obtain the latest version of this device specification before relying on any published information and before placing orders for products. Integrated Silicon Solution, Inc. does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless Integrated Silicon Solution, Inc. receives written assurance to its satisfaction, that: a.) the risk of injury or damage has been minimized; b.) the user assume all such risks; and c.) potential liability of Integrated Silicon Solution, Inc is adequately protected under the circumstances Integrated Silicon Solution, Inc. – www.issi.com Rev. A, 01/13/2015 5