 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
LT2940IDD Datasheet(PDF) 10 Page - Linear Technology |
|
||||||||||||||||||||||||||||||
LT2940IDD Datasheet(HTML) 10 Page - Linear Technology |
|
|
10 / 24 page  LT2940 10 2940f APPLICATIONS INFORMATION Introduction The LT2940 power and current monitor brings together circuits necessary to measure, monitor and control power. In circuits where voltage is constant, power is directly proportional to current. The LT2940 enables power moni- toring and control in applications where both the current and the voltage may be variable due to supply voltage uncertainty, component parametric changes, transient conditions, time-varying signals, and so forth. The LT2940’s four-quadrant multiplier calculates in- stantaneous power from its voltage sense and current sense inputs. Its output driver sources and sinks cur- rent proportional to power (magnitude and direction), which affords flexible voltage scaling, simple filtering and, into a reference, bipolar signals. Its onboard comparator is the final piece required for integrated power monitoring. In addition, the LT2940 provides a proportional-to-current output that allows for equally straightforward scaling, filtering and monitoring of the sensed current. Please note: although standard convention defines cur- rents as positive going into a pin (as is generally the case in the Electrical Characteristics table), the opposite is true of the PMON and IMON pins. Throughout this data sheet the power and current monitor output currents are defined positive coming out of PMON and IMON, respectively. Adopting this convention lets positive voltage differences at the current and voltage sense pins yield positive currents sourced from PMON and IMON that can be scaled to positive ground referenced voltages with a resistor. Multiplier Operation The LT2940 power and current monitor contains a four- quadrant multiplier designed to measure the voltage and current of a generator or load, and output signals propor- tional to power and current. Figure 1 shows a signal path block diagram. The operating ranges of the voltage sense and current sense inputs are included. To simplify the notation, the differential input voltages are defined as: VV = VV+ – VV– (1a) VI = VI+ – VI– (1b) The full scale output of the multiplier core is ±0.4V2, which the PMON output driver converts to current through a scale factor of KPMON. IPMON = KPMON • VV • VI (2) K µA V PMON = 500 2 (3) The voltage across the current sense input pins is converted to a current by the IMON output driver through the scale factor of GIMON. IIMON = GIMON • VI (4) G µA V IMON = 1000 (5) Both the PMON and IMON outputs reach full-scale at ±200μA. The headroom and compliance limits for the input and output pins are summarized in Table 1 for easy reference. It is important to note that the current sense inputs, I+ and I–, operate over a 4V to 80V range completely inde- pendent of the LT2940’s supply pin, VCC. Note also that the inputs accept signals of either polarity, and that the Figure 1. LT2940 Signal Path Diagram LT2940 VI = VI+ – VI– ±200mV (MAX) 2940 F01 ±200μA FULL-SCALE 7 8 11 10 PMON V + V – I + I – VV • VI = ±0.4V 2 FULL-SCALE 4 KPMON = 500 V2 μA ±200μA FULL-SCALE IMON 5 GIMON = 1000 V μA VV = VV+ – VV– ±8V (MAX) + – + – |
Similar Part No. - LT2940IDD |
|
Similar Description - LT2940IDD |
|
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
