摘要:
A resistor (R S ) is in series with the drain-source path of the MOS power transistor (M1). The supply terminal (s) of a transconductance operational amplifier (A) is connected to the output of a voltage-raising or charge pump (CP) circuit which can output a voltage higher than that of the voltage supply (V s ) to which the drain of the MOS transistor (M1) is connected. The inputs of the amplifier (A) are connected to the resistor (R S ) and its output is connected to the gate of the MOS transistor (M1) so that, in operation, the maximum current flowing through the power transistor (M1) is limited to a value proportional to a reference voltage (V R ).
摘要:
The circuit includes two output terminals (OUT1, OUT2) for connection to the terminals of a load (L), first and second pairs of electronic power switches (Q1, Q4; Q2, Q3) which are connected between the output terminals (OUT1, OUT2) and the two poles of a direct-current voltage supply (Vs) so as to form an H-shaped structure with the load (L), and a driver circuit (C1, C2) for selectively making the electronic power switches of the first pair (Q1, Q4) of the second pair (Q2, Q3) order to cause a current to flow through the load (L) in one direction or the other respectively, and for preventing the electronic switches (Q1, Q3; Q2, Q4) which are connected between the same output terminal (OUT1; OUT2) and the two poles of the voltage supply (Vs) from conducting simultaneously.
摘要:
A voltage-regulator circuit with a low voltage drop using a DMOS power transistor (PT) driven by a charge pump (CP) comprises two feedback loops: a first feedback loop having high gain and accuracy but low response speed, and a second feedback loop having a wide passband and fast response speed but low gain.
摘要:
A circuit for controlling the reserve lamp (LAMP) of a vehicle's fuel level indicator instrument (STR). The circuit uses a switch (SW1) controlled by an extremely asymmetric clock signal (CLK) periodically to switch, for a very short time, the signal (Rj) provided by the level sensor (SENS) towards a comparator (CMP) operable to compare this signal (Rj) with a threshold value (Rth) for the purpose of determining the state of the reserve lamp (LAMP).
摘要:
The electronic interface circuit can perform ratiometric processing and driving of a signal (Rj) generated by a fuel-level detector (GAL) of a vehicle. The circuit uses a current mirror (S) configured so as to send one half (Ij) of the output current (IL) to the input resistance (Rj) and one half of the output current (IL) to earth. The current mirror (S) is controlled by a voltage (Vj) taken from the input resistance (Rj) and by a voltage taken from a resistive divider (Ra1, Ra2), the latter voltage having been filtered by a low-pass filter (FIL), so as to achieve ratiometric processing of the input signal (Rj).
摘要:
The circuit includes two output terminals (OUT1, OUT2) for connection to the terminals of a load (L), first and second pairs of electronic power switches (Q1, Q4; Q2, Q3) which are connected between the output terminals (OUT1, OUT2) and the two poles of a direct-current voltage supply (Vs) so as to form an H-shaped structure with the load (L), and a driver circuit (C1, C2) for selectively making the electronic power switches of the first pair (Q1, Q4) of the second pair (Q2, Q3) order to cause a current to flow through the load (L) in one direction or the other respectively, and for preventing the electronic switches (Q1, Q3; Q2, Q4) which are connected between the same output terminal (OUT1; OUT2) and the two poles of the voltage supply (Vs) from conducting simultaneously.