Datasheet LTC6101, LTC6101HV (Analog Devices) - 9

link to page 9 link to page 9 LTC6101/LTC6101HV
PIN FUNCTIONS OUT:
Current Output. OUT will source a current that is
V+:
Positive Supply Pin. Supply current is drawn through proportional to the sense voltage into an external resistor. this pin.
The circuit may be configured so that the V–:
Negative Supply (or Ground for Single-Supply
LTC6101 supply current is or is not monitored along
Operation).
with the system load current.
To monitor only system load current, connect V+ to the more positive side of the
–IN:
The internal sense amplifier will drive IN– to the same sense resistor. To monitor the total current, including the potential as IN+. A resistor (RIN) tied from V+ to IN– sets LTC6101 current, connect V+ to the more negative side the output current IOUT = VSENSE/RIN. VSENSE is the voltage of the sense resistor. developed across the external RSENSE (Figure 1).
+IN:
Must be tied to the system load end of the sense resistor, either directly or through a resistor.
BLOCK DIAGRAM
ILOAD VSENSE – + V R V+ BATTERY SENSE RIN 10V LOAD –IN 5k – +IN 5k + 10V IOUT OUT R V OUT OUT = VSENSE x V– RIN LTC6101/LTC6101HV ROUT 6101 BD
Figure 1. LTC6101/LTC6101HV Block Diagram and Typical Connection APPLICATIONS INFORMATION
The LTC6101 high side current sense amplifier (Figure 1) tor, RIN, between IN– and V+ forces a potential across provides accurate monitoring of current through a user- RIN that is the same as the sense voltage across selected sense resistor. The sense voltage is amplified by RSENSE. A corresponding current, VSENSE/RIN, will a user-selected gain and level shifted from the positive flow through RIN. The high impedance inputs of the power supply to a ground-referred output. The output sense amplifier will not conduct this input current, signal is analog and may be used as is or processed with so it will flow through an internal MOSFET to the output pin. an output filter. The output current can be transformed into a voltage by
Theory of Operation
adding a resistor from OUT to V–. The output voltage is An internal sense amplifier loop forces IN– to have the then VO = V– + IOUT • ROUT. same potential as IN+. Connecting an external resis- Rev I For more information www.analog.com 9 Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS PIN FUNCTIONS BLOCK DIAGRAM APPLICATIONS INFORMATION TYPICAL APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS