19-1922; Rev 0; 1/01 MAX4295 Evaluation Kit The MAX4295 is a mono, switch-mode (Class-D) audio power amplifier intended for multimedia and generalpurpose high-power applications. It has greater than 87% efficiency and is capable of delivering 2W maximum continuous power to a 4Ω load. The MAX4295 evaluation kit (EV kit) is a fully assembled and tested surface-mount board. The EV kit is designed to be driven by the lineout or headphone jack of a CD player or to be directly connected to any audio source. The EV kit includes a volume control and a terminal block for quick speaker connection. Features ♦ 2W/Channel Output Power at 5V 0.7W/Channel Output Power at 3V ♦ Programmable PWM Oscillator Frequency Selection (125kHz, 250kHz, 500kHz, 1MHz) ♦ Low 0.4% THD+N (RL = 4Ω, fIN = 1kHz, fOSC = 250kHz) ♦ +2.7V to +5.5V Input Range ♦ Volume Control ♦ Fully Assembled and Tested Surface-Mount Board Component List DESIGNATION QTY DESCRIPTION C1, C8 2 0.1µF, 16V X7R ceramic caps (0603) Taiyo Yuden EMK107BJ104KA or Murata GRM39X7R104K016 C2 1 150pF, 50V NPO ceramic cap (0603) C3 1 5pF, 50V NPO ceramic cap (0603) C4, C12, C13, C14 0 Not installed C5, C6, C7, C9, C10 5 1µF, 10V X7R ceramic caps (0805) Taiyo Yuden LMK212BJ105KG or Murata GRM40X7R105K010 C11 1 330µF, 6.3V POSCAP Sanyo 6TPB330M J1 1 3.5mm stereo jack J2 JU1, JU2, JU3 1 2-position terminal block for speaker 3 3-pin jumpers L1, L2 2 15µH inductors Coilcraft DO3316P153 or Coiltronics UP2B-150 R1 1 10kΩ, thumbwheel potentiometer R2, R3 2 51kΩ ±5% resistors (0603) R4 1 100kΩ ±5% resistor (0603) U1 1 MAX4295EEE (16-pin QSOP) Ordering Information PART MAX4295EVKIT TEMP. RANGE IC PACKAGE 0°C to +70°C 16 QSOP Component Suppliers SUPPLIER PHONE FAX Coilcraft 847-639-6400 847-639-1469 Coiltronics 561-241-7876 561-241-9339 Murata 814-237-1431 814-238-0490 Sanyo 619-661-6835 619-661-1055 Taiyo Yuden 408-573-4150 408-573-4159 ________________________________________________________________ Maxim Integrated Products 1 For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Evaluates: MAX4295 General Description Evaluates: MAX4295 MAX4295 Evaluation Kit Quick Start Required Equipment • One 4Ω/8Ω speaker • One DC power supply capable of supplying +2.7V to +5.5V at 1.5A The MAX4295 EV kit is fully assembled and tested. Follow the steps below to verify board operation. Do not turn on the power supply until all connections are completed: 1) Connect the speaker to terminal blocks J2. 2) Connect an audio source, such as a CD player, to stereo jack J1 or the IN and AUDIO-GND pads. 3) Set the jumpers to the following positions: JU1: 2–3 (FS2 = low) fOSC = 250kHz JU2: 1–2 (FS1 = high) JU3: 1–2 (MAX4295 enabled) } 4) Connect a DC power supply to the VCC and GND pads. 5) Turn on the audio source. 6) Adjust the volume control, if necessary. Detailed Description ven by the lineout or headphone jack of a CD player or directly connected to any audio source. A thumbwheel potentiometer mounted to the board is provided to control volume. The EV kit is shipped with the components selected for driving 4Ω speakers with the MAX4295 set to unity gain. The gain can be increased by changing resistor R4. See the equation below for determining values: Gain = -R4 / (R2 + R3) = -R4 / 102kΩ To drive a speaker other than 4Ω, replace inductors L1 and L2 and capacitors C6 and C7. Refer to the MAX4295/MAX4297 data sheet for selecting the values. Jumper Selection Jumpers JU1 and JU2 control frequency select pins FS1 and FS2. See Tables 1 and 2 for the shunt positions. Note: The MAX4295 EV kit is optimized for a 250kHz switching frequency. Inductors L1 and L2 and capacitors C6 and C7 may need to be optimized for other switching frequencies. Refer to the MAX4295/MAX4297 data sheet for selecting the values. Jumper JU3 controls the shutdown pin (SHDN) on the MAX4295. See Table 1 for shunt positions. The MAX4295 EV kit is a mono, switch-mode (Class-D) audio power amplifier. The EV kit is designed to be dri- Table 1. Jumper Selection JUMPER JU1 JU2 JUMPER POSITION FUNCTION Table 2. Frequency Selection JU1 (FS2) JU2 (FS1) FREQUENCY 2–3 (GND) 2–3 (GND) 125kHz 1–2 Frequency select pin FS2 = VCC. 2–3 (GND) 1–2 (VCC) 250kHz 2–3* Frequency select pin FS2 = GND. 1–2 (VCC) 2–3 (GND) 500kHz 1–2* Frequency select pin FS1 = VCC. 1–2 (VCC) 1–2 (VCC) 1MHz 2–3 Frequency select pin FS1 = GND. 1–2* SHDN = high. MAX4295 enabled. 2–3 SHDN = low. MAX4295 disabled. Open Drive pad SHDN with an external signal. JU3 *Default position. 2 _______________________________________________________________________________________ MAX4295 Evaluation Kit Evaluates: MAX4295 C13 OPEN L1 15µH L2 15µH C6 1µF 1 GND J2 C7 1µF U1 SS 16 C8 0.1µF VCC 2 C11 330µF J1 3 MAX4295 PVCC PVCC C10 1µF 3 2 1 OUT+ OUT- PGND PGND 4 5 C14 OPEN IN R2 51kΩ R1 10kΩ C1 0.1µF C2 150pF AUDIO-GND 15 C9 1µF NC C5 1µF VCC GND VCM FS2 IN FS1 6 7 C3 5pF R4 100kΩ 8 AOUT SHDN C12 OPEN 14 13 12 11 C4 OPEN R3 51kΩ VCC 10 9 VCC 1 2 JU1 3 VCC 1 2 JU2 3 VCC 1 2 JU3 3 SHDN VCC VCC GND Figure 1. MAX4295 EV Kit Schematic _______________________________________________________________________________________ 3 Evaluates: MAX4295 MAX4295 Evaluation Kit ACTUAL BOARD DIMENSIONS: 2.4in x 2.9in ACTUAL BOARD DIMENSIONS: 2.4in x 2.9in Figure 2. MAX4295 Component Placement Guide— Component Side Figure 3. MAX4295 EV Kit PC Board Layout—Component Side ACTUAL BOARD DIMENSIONS: 2.4in x 2.9in Figure 4. MAX4295 EV Kit PC Board Layout—Solder Side Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 4 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.