DC2472A Analog Devices

DEMO MANUAL DC2472A 18-CELL STIMULUS BOARD DESCRIPTION Demonstration circuit 2472A is a USB-powered resistor- (e.g. DC2701A) should be torqued to 0.22-0.25Nm. string, voltage ladder with variable output. The DC2472A See Figure 1 for example installations. provides a simple battery stack simulator for connection 2. In the case of a 15-cell demo (e.g. for LTC6812), the directly to most of Linear Technologys LTC68xx battery pinout requires every sixth tap pair to be shorted over. stack monitor demo boards. To accomplish this, place JP19, JP20, and JP21 to the Using the 5V from a USB charger, the DC2472 generates 15 position. In all other usages, leave those jumpers an isolated high voltage from ~25V to ~75V, applied to in the 18 position. Note that cell voltages will increase a resistor string generating 18 voltages taps. These taps 20% with placement of jumpers in the 15 position provide a simulation of a string of series connected bat- due to the reduced division factor. tery cells, each tap pair providing nominally the same 3. A USB to USB MICRO-B cable (like non-Apple cell virtual cell voltage. The input voltage to the resistor string phone charger) provides a simple means of powering is adjustable by an on-board potentiometer to furnish a the DC2472A from a 1A USB charger (some computer divided output voltage in a range of about 1.5V-4.2V per ports may not provide adequate current for stable cell to demonstrate operation at conditions comparable output levels). Alternatively, a 5V bench power supply to a wide range of cell chemistries. can be connected to the power input turrets (+5V & +5V COM) with clip-leads. Note that the +5V connec- CONNECTION TO AN LTC68XX DEMO-BOARD tions are isolated with respect to the GND turret of the DC2472A, so the +5V COM and GND cannot be used 1. The back side of the DC2472A shows where the interchangeably. LTC68xx demo board connectors should be attached. Simply line up the finger contacts with the associated WARNING THIS BOARD GENERATES VOLTAGE POTEN- screw terminal connector according to whether the TIALS UP TO 80V connector is a 16- or 19-contact model. The screws Design files for this circuit board are available at for securing the connections should be facing the com- DEMO MANUAL DC2472A QUICK START PROCEDURE 1. Power up the DC2472A from the USB cable or bench 4. Operate the LTC68xx demo as applicable. Note that supply. resistor-string battery simulations (and DC2472A in particular) cannot generally generate currents suitable 2. Once powered, the Blue LED1 should illuminate. for properly demonstrating cell-balancing activity. 3. Adjust potentiometer to provide a desired equivalent 5. Jumpers JP0 through JP18 may be used to discon- cell voltage as shown in Figure 2. Note that there will nect particular tap signals for demonstrating open- be some variation in voltages amongst cells due to wire scenarios. Relocating a particular jumper to the component tolerances. NC position will disconnect a cell path to simulate a broken connection. Figure 2. Cell Voltage Setting dc2472af 2