C1608X7R1H104K-T

® ISL85001EVAL1Z: 1A Regulator Standard Buck PWM Application Note December 1, 2008 A N1443.0 Description The ISL85001EVAL1Z REV A kit is intended for use by individuals with requirements for Point-of-Load applications sourcing from 4.5V to 25V. The ISL85001EVAL1Z evaluation board is used to demonstrate the performance of the ISL85001 standard buck regulator. The ISL85001 is offered in a 4mmx3mm 12 Ld DFN package with 1mm maximum height. The complete converter occupies less than 0.425in2 area. Recommended Equipment The Following Materials are Recommended to Perform Testing: • 0V to 25V Power Supply with at Least 5A Source Current Capability, Battery, Notebook AC Adapter • One Electronic Load Capable of Sinking Current up to 5A • Digital Multimeters (DMMs) • 100MHz Quad-Trace Oscilloscope • Signal Generator Features • Standard Buck Controller with Integrated Switching Power MOSFET • Integrated Boot Diode • Input Voltage Range - Fixed 5V ±10% - Variable 5.5V to 25V • PWM Output Voltage Adjustable from 0.6V to 19V with Continuous Output Current up to 1A • Voltage Mode Control with Voltage Feed-Forward • Fixed 500kHz Switching Frequency • Externally Adjustable Soft-Start Time • Output Undervoltage Protection • Enable Inputs • PGOOD Output • Overcurrent Protection • Thermal Overload Protection • Internal 5V LDO regulator Quick Setup Guide 1. Ensure that the circuit is correctly connected to the supply and loads prior to applying any power. 2. Connect the bias supply to VIN, the plus terminal to TP1 (VIN) and the negative return to TP2 (GND). 3. Verify that SW1 is on ENABLE. 4. Turn on the power supply. 5. Verify the PG is on and the output voltage is 2.5V for VOUT(TP3). Evaluating the Other Output Voltage The ISL85001EVAL kit outputs are preset to 2.5V; however, it can be programmed using resistor dividers using Equation 1: R 1 ⋅ 0.6V R 2 = ---------------------------------V OUT – 0.6V (EQ. 1) The output voltage programming resistor R2 will depend on on the feedback resistor R1, as referred to in Figure 1. The value of R1 is typically between 1kΩ and 10kΩ. If the output voltage desired is 0.6V, then R2 is left opened. VOUT R1 + - Applications • General Purpose • WLAN Cards-PCMCIA, Cardbus32, MiniPCI Cards-Compact Flash Cards EA • Hand-Held Instruments • LCD Panel • Set-top Box 0.6V REFERENCE R2 What’s Inside The Evaluation Board Kit contains the following materials: • The ISL85001 EVAL REV A board • The ISL85001 datasheet • This EVAL KIT document SW1 1 FIGURE 1. EXTERNAL RESISTOR DIVIDER TABLE 1. SWITCH 1 SETTINGS ENABLE SW1 OPERATING MODE Enable or disable the buck controller 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2008. All Rights Reserved All other trademarks mentioned are the property of their respective owners. Application Note 1443 ISL85001EVAL1Z Schematic VDD 2.43K R20 R1 2 C1 1 R21 10K 30K C2 2200PF 47PF R3 301 R4 R2 10K 2 2 C3 1 VIN 1 D3 470PF 1 TP1 1 OPEN 10UF C11 1 220UF C10 C20 COMP 1 TP16 3.16K GND 1 TP2 FB 2 2N7002 PG 1 Q4 2 1 FB COMP SS EN PG VIN VIN PHASE PHASE BOOT VDD 12 11 2 2 2 U1 3 C4 1 L1 3 10 9 PHASE 1 1 VOUT 1 TP3 0.1UF 47UF C13 C12 C21 5 67 8 2 3 4 SP2 OPEN EN PG 4 BOOT 1 1 C9 1 1 D1 13 2 2 1UF C8 2 EP 2 1 3 GND 0.1UF 1 2 4 SP1 TP4 ISL8500IRZ VDD TP13 R30 OPEN 2 VIN 100K R12 POPULATE R30 IF VIN