TS1100 Current-Sense Amplifier Demo Board FEATURES DESCRIPTION The demo board for the TS1100 is a completely RSENSE: 50m 1% assembled and tested circuit board that can be used Fully Assembled and Tested for evaluating the current-sense amplifier for all (4) 2in x 2in 2-layer circuit board gain options i.e., 25V/V, 50V/V, 100V/V, and 200V/V. COMPONENT LIST The board is configured with an RSENSE =R1=50m resistor. The board has a dedicated RS+=VBATT, RS-=LOAD, and output voltage OUT=VOUT test DESIGNATION QTY DESCRIPTION C1 1 0.1F 10% points. For additional information, refer to the TS1100 capacitor (0805) product datasheet. C2 1 47nF 10% capacitor (0805) All TS1100s are available in a PCB-space saving 5- R1 1 50m 1% (0805) lead SOT23 surface-mount package. U1 1 TS1100-25DB/ TS1100-50DB/ TS1100-100DB/ Product data sheets and additional documentation TS1100-200DB can be found at www.silabs.com. VBATT, VOUT, 3 Test points LOAD ORDERING INFORMATION Order Number Description TS1100-25DB TS1100-50DB TS1100-XXX Demo Board TS1100-100DB TS1100-200DB DESCRIPTION Figure 1. TS1100 current-sense amplifier circuit Page 1 2014 Silicon Laboratories, Inc. All rights reserved. TS1100 Current-Sense Amplifier Demo Board The demo board includes an on-board 0.1F negative terminal to the adjacent test point decoupling capacitor at the V input pin and a labeled GND. BATT 47nF capacitor at the VOUT output pin. Depending on 5) Based on the selected gain option of the current the load current desired, an external resistor or active sense amplifier, select the load resistor or an load is to be connected to the LOAD pin. active load according to Table 2. Connect one end of this resistor or active load to the pad QUICK START PROCEDURE labeled LOAD and the other end to the adjacent pad labeled GND. Required Equipment 6) Turn on the power supply and observe the output voltage at V . The expression for the TS1100s OUT TS1100 demo board output voltage is given by: V = I x 50m x R /R1 A DC Power Supply, an HP Model HP6624A or OUT LOAD OUT equivalent where the TS1100s internal ROUT and R1 resistor values are listed in Table 3. Two digital voltmeters Load resistor or an active load (value varies GAIN(V/V) R1 () ROUT () depending on ILOAD desired) 25 400 10k 50 200 10k Signal Eval board 100 100 10k RS+ VBATT 200 100 20k RS- LOAD Table 3. TS1100s Internal Gain Setting Resistors OUT VOUT (typical values) GND GND 7) The TS1100s actual output voltage V will OUT Table 1. Demo board test points depend on the TS1100s actual offset voltage V , its gain error GE, sense resistor (R ) OS SENSE MAX GAIN VBATT ILOAD RLOAD VOUT tolerance of 1%, and the load resistor VSENSE (V/V) (V) (mA) () (V) tolerance/active load accuracy. (mV) 25 6 1600 3.75 2 80 50 6 800 7.5 2 40 100 6 400 15 2 20 200 6 200 30 2 10 Table 2. Demo board test set-up per gain setting To evaluate the TS1100 current-sense amplifier circuit, the following steps are to be performed: 1) Before connecting the DC power supply to the demo board, turn on the power supply, set the DC voltage to 6V, set its short circuit current limit to 10% higher than the maximum load current in the application, and then turn it off. 2) Connect the DC power supply positive terminal to the pad labeled VBATT and its negative terminal to the adjacent pad labeled GND. 3) Connect a digital voltmeter to the test points labeled TP+ and TP- to measure V . SENSE 4) Connect the positive terminal of a second digital voltmeter to the test point labeled V and the OUT Page 2 Silicon Laboratories, Inc. TS1100-EVB Rev. 1.0 400 West Cesar Chavez, Austin, TX 78701 +1 (512) 416-8500 www.silabs.com