JPH11168641A - Fpu controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate wasteful power consumption in a power supply circuit for a head part side and to miniaturize the circuit from the standpoint of the breakdown voltage of capacitors and semiconductors. SOLUTION: A DC power supply voltage supplied from a control section, while being superimposed on an IF signal in a head section is received by a CPU, which transfers voltage data to the control section via a medium. On the other hand, a CPU 2 of the control section processes CPU communication data sent from the head section, the data are D/A-converted (3) and an analog signal is obtained. The obtained DC: voltage is fed to a voltage setting circuit 6 of a stabilizing power supply circuit 1. When a DC power supply voltage fed to the head section is changed, a power supply output voltage of the control section is controlled, and the power supply voltage fed to the head section is kept constant, even if the length between the control section and the head is changed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply used for an FPU device.

[0002]

2. Description of the Related Art Conventionally, an FPU device is often used, for example, by connecting a control unit 10 and a head unit 11 with a cable 12 as shown in FIG. In this case, the power supply system superimposes a DC voltage of, for example, +35 V on the IF signal from the control unit 10 and sends the signal to the head side through a cable.
3 is driving. On the other hand, in order to enable head remote control such as channel switching and SHF power switching from the control unit 10, communication control between the control unit and the head is performed by the CPUs 14 and 15. The data transmission / reception interface uses the modem circuits 16 and 17, and generally employs the FSK modulation / demodulation method.

For example, a 5D-2W coaxial cable is generally used as a cable connecting the control unit and the head, and the maximum usable cable length is, for example, 400 m.

The DC resistance of a 5D-2W coaxial cable is, for example, about 6.8 ohms at 400 m. Therefore, the DC voltage supplied from the control unit to the head drops due to the DC resistance of the coaxial cable. For example, if the current flowing through the cable (current consumption of the head) is 2A, 1
The voltage drops by 3.6V. For this reason, the DC voltage reaching the conventional head is taken into the CPU, the voltage data is transferred to the control unit, and the meter is swung based on this data so that the control unit can monitor the head reaching voltage.

[0005]

In the above-mentioned prior art, when the connecting cable between the control unit and the head is short, for example, when it is used at 100 m, the DC resistance of the cable is about 1.7Ω and the drop is about 1.7 Ω. The voltage is 1
It is 3.4V with respect to 3.6V, and a difference of about 10V occurs. Therefore, in the head-side power supply circuit, when the cable length is short, the voltage difference of 10 V is wasted. It is also disadvantageous in terms of the withstand voltage rating of electrolytic capacitors and semiconductors. The present invention seeks to eliminate these disadvantages.

[0006]

According to the present invention, in order to achieve the above object, a head-side DC voltage is read into a head-side CPU, and data is transferred to the control-side CPU via a modem. The control section converts the DC voltage data sent from the head section into a DC voltage by a DA converter. Therefore, the DC input voltage supplied to the head is
When the output voltage of the DA converter changes due to the difference in the length of the control unit and the head connection cable, the output voltage also changes. After performing the gain adjustment on the DC voltage obtained by the DA conversion, the DC voltage is supplied to the control unit of the stabilized power supply circuit to change the output DC voltage.

[0007] For example, if the connection cable between the control unit and the head is 4
When the cable length is 100 m, the DC voltage output from the power supply of the control unit is about +35 V, and when the cable length is 100 m, the voltage is about +25 V.
Control to V.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. 1 shown in FIG. 1 is an embodiment of a power supply circuit of a control unit, which is a general switching power supply. In the configuration of the present invention, 2 to 5 circuits are added to the switching power supply circuit. The operation is performed as described with reference to FIG.
DC input voltage data is transferred to the PU 2 from the CPU of the head unit. This data content is supplied to the DA converter 3 and converted into an analog signal. Therefore, when the DC voltage supplied to the head unit changes, the DC data transferred to the CPU of the control unit changes, and the DC output voltage of the DA converter 3 also changes. The DC output voltage is amplified by the amplifier 4 and the shift of the DC potential can be adjusted. The output of the amplifier 4 is supplied to the control unit voltage setting circuit 6 of the control unit power supply circuit 1 via the switch circuit 5. An ON / OFF command signal is supplied from the CPU 2 to the switch circuit 5, and a preset voltage is supplied to the voltage setting circuit 6 of the power supply circuit 1 until the CPU data is established at the time of POWER ON, and the ON command signal is supplied. When it comes out, the control voltage is supplied.

[0009]

According to the present invention, when the control unit and the head unit are connected by a coaxial cable in an FPU device,
Even if the cable length changes, the output voltage of the control unit side power supply is controlled so that the DC voltage supplied to the head unit becomes constant. Therefore, in the power supply circuit on the head side, there is an advantage that unnecessary power consumption can be eliminated and miniaturization can be achieved in terms of withstand voltage of the capacitor and the semiconductor.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of the present invention.

FIG. 2 is a system diagram in a state where a control unit and a head unit are connected.

[Explanation of symbols]

1: stabilizing power supply circuit of control unit, 2: control unit CPU circuit,
3: DA converter, 4: amplifier, 5: switch circuit.

Claims (2)

[Claims] In a control unit of an FPU device, a power supply unit for obtaining a DC voltage to be supplied to a head unit of the FPU device. An FPU control device characterized by changing to: 2. A DC power supply voltage input at a head unit of an FPU device is taken into a CPU of the head unit, data is transferred to a control unit via a modem, and data received by the control unit is processed by the CPU of the control unit. The DC voltage is converted by a DA converter into an analog signal to obtain a DC voltage, and the obtained DC voltage is supplied to a voltage setting circuit of a power supply circuit unit of a control unit. When the voltage supplied to the head unit changes due to a change in the data, the communication data is sent to the control unit using the CPU communication function, and the power supply voltage is controlled based on the data.
U control device.