DC2369A Analog Devices

DEMO MANUAL DC2369A Low Power Wireless Current Sense Introduct I The DC2369A demo circuit is a reference design that (LTP5901-IPM) runs the application, provides the wire- implements a wireless current sense solution using less mesh connectivity and communicates with a central Linear Technologys low power integrated circuits. The only network manager. A switching power supply (LTC3335) external connection needed is the current to be measured, counts the cumulative charge drawn from the included allowing this circuit to be inserted at any voltage level or battery while also regulating the output voltage for the rest isolation level. of the application. Table 1 shows featured components used along with their function. The design combines components for current measure- ment, power management and wireless mesh networking. Design files for this circuit board are available at A micro-power zero-drift op amp (LTC 2063) amplifies DEMO MANUAL DC2369A 2369A E I S A Ju MPEr S 1. Set the slide switch SW1 to ON to power on the circuit. to 1A full-scale current, developing a 10mV voltage DC2369A is powered from its included two AAA batteries drop across the sense resistor. Connect the current to and therefore does not need an external power supply. be measured using the banana connectors (J2 and J3). The slide switch asserts the enable pin of the LTC3335. Set jumpers JP1 and JP2 to the INT position (to use the You may verify correct operation of the power supplies internal sense resistor). See Figure 1. by measuring (on the back of the circuit board) that 3. Alternatively, DC2369A can be used to measure the volt- V GND = 3.3V and V GND = 3.0V. DD REF age across an external sense resistor. In this case, set 2. The only external connection needed to the DC2369A is jumpers JP1 and JP2 to EXT, and connect the voltage + for the current to be measured. The DC2369A circuitry to be measured to the turrets labeled V and V . IN IN does not draw its power from this current it only uses it The preconfigured DC2369A firmware and software to develop a small voltage drop across the included 10m will still assume a 10mV full-scale input voltage and sense resistor. The DC2369A is designed to measure up report that as a 1A full-scale current. See Figure 2. Figure 1. DC2369A Connections and Jumpers for Internal Sense Resistor Figure 2. DC2369A Connections and Jumpers for External Sense Resistor dc2369af 2 nd on ct conn dc