IS31AP2145A 2.9W 5V MONO CLIP-LESS & FILTER-LESS CLASS-D AUDIO POWER AMPLIFIER DESCRIPTION RECOMMENDED EQUIPMENT The IS31AP2145A is a 2.9W 5.0V mono, clip-less, 5.0V, 2A power supply filter-less, high efficiency Class-D audio power Audio source (i.e. MP3 player, Notebook PC, etc.) amplifier with automatic gain control. 8 or 4 speakers The IS31AP2145A integrates an AGC (Automatic Gain Control) function to automatically prevent distortion of ABSOLUTE MAXIMUM RATINGS the audio signal by which we can enhance audio quality and also protect the speaker from damage at 5.5V power supply high power levels. The AGC function and its attack time/release time are selectable via the CTRL pin. The Caution: Do not exceed the conditions listed above, otherwise the board will be damaged. IS31AP2145A also provides thermal and over current protection functions. The demo board has four modes (AGC1, AGC2, AGC PROCEDURE OFF, and SHUTDOWN) to test the functionality of the IS31AP2145A. The IS31AP2145A demo board is fully assembled and tested. Follow the steps below to verify board operation. FEATURES Caution: Do not turn on the power supply until all connections Operating from V = 2.7V ~ 5.5V are completed. CC Filter-less Class-D architecture 1) Connect a 4 (or larger) speaker across the OUT- AGC enable/disable function terminal and OUT+ terminal or the RCA female 2.7W into 4 at 5.0V (10% THD+N) connector (SPK CON3). Minimum external components 2) Connect the ground terminal of the power supply High efficiency: 90% to the GND (TP2) and the positive terminal to the VCC (TP1). Or connect DC power to connector Click-and-pop suppression (DC IN) with a 2.5 mm jack. Short-circuit and thermal protection 3) If the audio source is differential, remove jumper Space-saving UTQFN-9, 1.5mm 1.5mm JP1, connect the negative of the audio source to the IN- terminal, and connect the positive of the QUICK START audio source to IN+ terminal. 4) 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 -40C ~ +85C (Industrial) UTQFN-9, Lead-free Table 1: Ordering Information For pricing, delivery, and ordering information, please contact Lumissils analog marketing team at analog Lumissil.com or (408) 969-6600. Lumissil Microsystems www.lumissil.com 1 Rev. A, 01/13/2015 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 The evaluation boards high-pass filter consists of the to read the status of the four buttons which select input capacitors C (C or C ) and R (IS31AP2145A IN 4 5 IN between the different modes shown in Table Co1 internal resistance (28.5k) + (R or R ). The filters 1 2 below. The current operating mode is indicated by the corner frequency, f , is determined by Equation (1). C illuminated LED above the appropriate button. The 1 default mode is AGC1 enabled. f (1) c 2R C IN IN Table 2 Mode settings The corner frequency can be adjusted by replacing the CTRL1 CTRL2 Mode R or R 0 resistors with a larger resistor value or by 1 2 H H AGC1 increasing/decreasing the C or C capacitance. 4 5 H GND AGC2 GND H AGC OFF SHUTDOWN MODE GND GND Shutdown The SHUTDOWN button selects the power-down See the IS31AP2145A datasheet for mode mode of the IS31AP2145A. configuration details. Note: The IS31AP2145A Mode setting is controlled by the onboard LPC922 MCU. TP1 CON1 VCC VCC DC IN C1 C2 C3 C10 10uF 0.1uF 1uF 1uF TP2 TP3 U1 CON2 AUDIO IN IN- C4 10nF R1 0R A1 TP5 IN+ CON3 TP4 A3 OUT+ OUT+ IN+ C5 10nF R2 0R C1 SPK IN- TP7 C3 OUT- OUT- JP1 C2 Speaker R3 68K SD CTRL CTRL1 CLOSE=SE TP6 33K R4 CTRL2 C11 IS31AP2145A R5 0.1uF 22K U3 3V VCC 4 3V RST U2 7 OSC2 19 R10 1K D1 R6 R7 R8 R9 P0.2 C8 C7 6 10K 10K 10K 10K OSC1 1uF 10nF K1 18 R11 1K D2 P0.3 1 AGC1 P1.6 K2 17 P0.4 C9 2 3V P1.7 AGC2 K3 16 P0.5 3 P0.0 AGC OFF K4 15 0.1uF PAM3101 VDD 20 P0.1 SHUTDOWN 14 R12 1K D3 VCC P0.6 C6 8 INT1/P1.4 1uF 13 R13 1K D4 9 T1/P0.7 INT0/P1.3 10 12 T0/P1.2 TXD/P1.0 CTRL2 5 11 GND RXD/P1.1 CTRL1 LPC922 Figure 2: IS31AP2145A Application Schematic Lumissil Microsystems www.lumissil.com 2 Rev. A, 01/13/2015 A2 VDD B1 GND B3 B2 GND VREF 1 5 VddVout 2 GND 3 4 EN BP