TS1103 Bidirectional Current-Sense Amplifier Demo Board FEATURES RSENSE: 50m 0.5% Fully Assembled and Tested 2in x 2in 2-layer circuit board COMPONENT LIST DESIGNATION C2 QTY 1 R1 1 U1 1 VDD, VBATT, VOUT, SIGN, LOAD 5 DESCRIPTION 47nF 10% capacitor (0805) 50m 0.5% (0805) TS1103-25DB/ TS1103-50DB/ TS1103-100DB/ TS1103-200DB Test points DESCRIPTION The demo board for the TS1103 is a completely assembled and tested circuit board that can be used for evaluating the bidirectional current-sense amplifier for all (4) gain options; i.e., 25V/V, 50V/V, 100V/V, and 200V/V. The board is configured with an RSENSE =R1=50m resistor. The board has a dedicated RS+=VBATT, RS-=LOAD, output voltage OUT=VOUT, VDD, and SIGN test points. For additional information, refer to the TS1103 product data sheet. All TS1103s are available in a PCB-space saving 6-lead SOT23 surface-mount package. Product data sheets and additional documentation can be found at www.silabs.com. ORDERING INFORMATION Order Number TS1103-25DB TS1103-50DB TS1103-100DB TS1103-200DB Figure 1. TS1103 Bidirectional Current-Sense Amplifier Circuit Description TS1103-XXX Demo Board Figure 2. TS1103 Demo Board Page 1 (c) 2014 Silicon Laboratories, Inc. All rights reserved. TS1103 Bidirectional Current-Sense Amplifier Demo Board DESCRIPTION The TS1103 demo board includes decoupling capacitor pads, C1, at the VBATT input pin and a 47nF capacitor at the VOUT output pin. Because the TS1103 is a bidirectional current-sense amplifier, the demo board can be set-up to sense current in both directions. Please refer to Table 2 for the proper connections of VBATT and LOAD test points. The direction of the current is known based on the voltage level of the SIGN pin. If VRS+>VRS-, the SIGN pin is a logic HIGH or VDD voltage. If VRS->VRS+, the SIGN pin is a logic LOW or GND voltage. A VDD test point is available and powers the internal comparator that monitors the direction of the load current. The output voltage of the comparator is the voltage on the SIGN pin. QUICK START PROCEDURE Required Equipment A TS1103 demo board A dual output, DC power supply, an HP Model HP6624A or equivalent Three digital voltmeters A load resistor or an active load (value varies depending on ILOAD desired) MAX VSENSE (mV) 25 6 1600 1.8 3.75 2 80 50 6 800 1.8 7.5 2 40 100 6 400 1.8 15 2 20 200 6 200 1.8 30 2 10 Table 3. Demo Board Test Set-Up Per Gain Setting Page 2 ILOAD (mA) VDD (V) RLOAD () 2) For applications where VRS+>VRS-, connect the 6V DC power supply positive terminal to the test point VBATT and its negative terminal to the test point GND. Connect the 1.8V power supply positive terminal to the test point VDD and its negative terminal to the test point GND. See Table 2 for applications where VRS->VRS+. 3) Connect a digital voltmeter to the test points TP+ and TP- to measure VSENSE. 4) Connect the positive terminal of a second digital voltmeter to the test point VOUT and the negative terminal to the test point GND. 5) To monitor the direction of the current, connect the positive terminal of a third digital voltmeter to the test point SIGN and the negative terminal to the test point GND. 7) Turn on the power supply and observe the output voltage at VOUT. The expression for the TS1103's output voltage is given by: Test Point VRS+>VRSVRS->VRS+ input voltage load VBATT load input voltage LOAD Table 2. VBATT and LOAD Test Point Connections Per ILOAD Direction VBATT (V) 1) Before connecting the DC power supply to the demo board, turn on the power supply, set the DC voltage to 6V on one output and the other to 1.8V. Set the short circuit current limit on each output to 10% higher than the maximum load current in the application, and then turn it off. 6) Based on the selected gain option of the current sense amplifier, select the load resistor or an active load according to Table 3. Connect one end of this resistor or active load to the test point LOAD and the other end to the test point GND. Signal Demo board VBATT RS+ LOAD RSVOUT OUT GND GND VDD VDD SIGN SIGN Table 1. Demo Board Test Points GAIN (V/V) To evaluate the TS1103 bidirectional current-sense amplifier circuit, the following steps are to be performed: VOUT (V) VOUT = ILOAD x50mx ROUT RGAIN[A/B] where the TS1103's internal ROUT and RGAIN[A/B] resistor values are listed in Table 4. GAIN(V/V) RGAIN[A/B] () ROUT () 25 400 10k 50 200 10k 100 100 10k 200 100 20k Table 4. TS1103's Internal Gain Setting Resistors (typical values) TS1103-EVB Rev. 1.0 TS1103 Bidirectional Current-Sense Amplifier Demo Board 8) The TS1103's actual output voltage VOUT will depend on the TS1103's actual offset voltage VOS, its gain error GE, sense resistor (RSENSE) tolerance of 1%, and the load resistor tolerance/active load accuracy. Figure 3. Top Layer Component View Note: For applications where VRS->VRS+, connect test points VBATT and LOAD based on Table 2 and follow the steps above. Figure 4. Top Layer Trace View Figure 5. Bottom Layer (GND) Silicon Laboratories, Inc. 400 West Cesar Chavez, Austin, TX 78701 +1 (512) 416-8500 www.silabs.com Page 3 TS1103-EVB Rev. 1.0 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Silicon Laboratories: TS1103-50DB TS1103-200DB TS1103-25DB TS1103-100DB