Application Note 1877 Author: Philip McKenzie ZL8800-2CH-DEMO1Z Demonstration Board The ZL8800 is a digital power conversion and management IC Target Specifications that combines an efficient step-down DC/DC converter with V = 12V key power and thermal management functions in a single IN package. The ZL8800 incorporates compensation-free V = 1.2V/30A max and 1.0V/30A max OUT ChargeMode control to achieve single-cycle transient response. f = 512kHz SW The ZL8800-2CH-DEMO1Z demonstration board is a 6-layer Efficiency: 91% at 20A board demonstrating 2 independent 30A synchronous buck Output Ripple: 1% converters. Sequencing, tracking, margining, plus other features can be evaluated using this board. Dynamic response: 1% (50% to 100% to 50% load step, di/dt = 10A/s) A USB to PMBus adapter board is used to connect the Board temperature: +25C demonstration board to a PC. The PMBus command set is accessed by using the Zilker Labs PowerNavigator evaluation software from a PC running Microsoft Windows. Functional Description The ZL8800-2CH-DEMO1Z provides all circuitry required to Key Features demonstrate the features of the ZL8800. The ZL8800-2CH-DEMO1Z has a functionally-optimized ZL8800 2 independent 30A synchronous buck converters with circuit layout that allows efficient operation up to the compensation-free ChargeMode control maximum output current. Designed to be easy to use and modify. Optimized for small circuit footprint and dynamic response A majority of the features of the ZL8800, such as compensation-free ChargeMode control, soft-start delay and Configurable through PMBus ramp times, supply sequencing, voltage tracking, and voltage V range of 6.5V to 14V, V adjustable from 0.54 to 5.5V IN OUT margining are available on this demonstration board. For Enable switches and power-good indicators voltage tracking and sequencing demonstration, the board can be connected to any other Zilker Labs demonstration board Ordering Information that supports the Digital-DC (DDC) bus. Figure 1 shows a simplified schematic diagram of the PART NUMBER DESCRIPTION ZL8800-2CH-DEMO1Z board. ZL8800-2CH-DEMO1Z ZL8800 Demonstration Kit (EVB, USB Adapter, Cable) VIN 4.5V - 14V VDD VDRV VDRV ZL8800 VOUT1 VOUT0 BST PWM PWMH1 PWMH0 PWM BST 0.54V 0.54V 5.5V 5.5V Vsw EN PWML1 PWML0 EN Vsw GND GND ISENA1 ISENA0 ISENB1 ISENB0 VSENP1 VSENP0 VSENN1 VSENN0 Inter-Device DDC Communication EN0 EN1 Control & SDA Status PG0 SCL PMBus PG1 SALRT GND FIGURE 1. ZL8800-2CH-DEMO1Z SIMPLIFIED SCHEMATIC November 14, 2013 CAUTION: These devices are sensitive to electrostatic discharge follow proper IC Handling Procedures. 1 1-888-INTERSIL or 1-888-468-3774 Copyright Intersil Americas LLC 2013. All Rights Reserved AN1877.1 Intersil (and design), PowerNavigator and Digital-DC are trademarks owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. Vin DrMOS VDD VDD DrMOS VinApplication Note 1877 The hardware enable function is controlled by toggle switches on Quick Start Guide the ZL8800-2CH-DEMO1Z board. The power-good (PG) LEDs indicate the correct state of PG when external power is applied to Stand Alone Operation the ZL8800-2CH-DEMO1Z board and the corresponding output is 1. Set ENABLE switch to DISABLE functioning properly. The right angle headers at opposite ends of 2. Apply load to VOUT0 and/or VOUT1 the board are for connecting a USB to PMBus adapter board or for daisy chaining multiple demonstration boards together to 3. Connect the USB to PMBus adapter board to J8 (labeled build multi-output configurations. DONGLE) of ZL8800-2CH-DEMO1Z 4. Connect supplied USB cable from computer to USB to PMBus Figures 2 and 3 show the detailed demonstration circuit. Figure 2 adapter board shows the ZL8800 IC with its minimal component count to realize a 30A output on each buck converter. Figure 3 has 5. Connect power supply to VIN (supply turned off) interface circuitry unique to the demonstration board that is not 6. Turn power supply on typically contained in a users application circuit. Figures 4 7. Set ENABLE switch to ENABLE through 10 show typical performance data, and Figures 15 8. Monitor ZL8800-2CH-DEMO1Z board operation using an through 22 demonstrate the PCB board layout, which includes oscilloscope the board fabrication notes. The default configuration file is shown on page 6, and the Bill of Materials (BOM) is included for USB (PMBus) Operation reference beginning on page 5. 1. Set ENABLE switch to DISABLE Operation 2. Apply load to VOUT and/or VOUT1 3. Connect power supply to VIN (supply turned off) PMBus Operation 4. Turn power supply on The ZL8800 utilizes the PMBus protocol. The PMBus functionality can be controlled via USB from a PC running the PowerNavigator 5. Connect USB to PMBus adapter board to J8 of ZL8800-2CH-DEMO1Z evaluation software in a Windows XP or Windows 7 operating systems. 6. Connect supplied USB cable from computer to USB to PMBus adapter board. Install the evaluation software from the following Intersil Install the PowerNavigator evaluation software from the website: following Intersil website: