JPS5896269U - voltage detection circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

FIG. 1 shows a conventional voltage detection circuit. 1 is a P-channel transistor, R is an attached variable resistor made outside the IC, 2
is a P-channel transistor, 3 is an N-channel transistor, and 2.3 transistors form a complementary inverter.
0 is the output of the voltage detection circuit, +DD is the positive potential with respect to negative ground, VG is the drain voltage of the transistor 1, and the gate voltage of the complementary inverter of the transistor in the next stage 2.3. FIG. 2 is an explanatory diagram of the temperature characteristics of the circuit shown in FIG. 1. vG, ■□ are the same as in Figure 1, VTP is the threshold voltage of the P-channel transistor 1 in Figure 1, curve 6 is the vG-VDD function curve at room temperature, and curve 7 is the high temperature of the function curve. The curve 8 is the low temperature state of the function curve, and the straight line 9 is the transition voltage V of the complementary inverter consisting of 2.3 transistors in FIG. ★-v
DD line, region 4 indicates that the P-channel transistor of FIG. 1 is used in a saturated state, and region 5 indicates that it is used in an unsaturated state. Point 10 is the intersection of curve 6 and straight line 9, and indicates detection voltage VDD10 at room temperature. Point 11 is at the intersection of curve 7 and straight line 9, and the detected voltage V at high temperature
DD11 is shown. Point 12 is the intersection of curve 8 and straight line 9, and indicates detection voltage vDD12 at low temperature. Point 1j is curve 6.
7. It is the only point where the temperature characteristic is 0 at the intersection of 8. FIG. 3 shows the voltage detection circuit of the present invention. 22°24 is P
channel transistor, 23 is a ball channel transistor, 0. R1+vDD is the same as in Figure 1, ■, is the drain voltage of the P-channel transistor 22, the gate voltage of the N-channel transistor 23, A is the drain node of the transistor 23.24, and B is the complementary type of the first stage. Gate node of both P-channel and N-channel transistors of the inverter. FIG. 4 shows the voltage detection circuit of the present invention. 25°27 is N
channel transistor, 26, P-channel' transistor, 0. R, +VDD are the same as in Figure 1, vG is the drain voltage of N-channel transistor 25, gate voltage of P-channel transistor 26, A is the drain node of transistor 26.27, B is the same as in Figure 3 . FIG. 5 is an explanatory diagram of the circuit shown in FIG. 3. VG
10VDD is the same as in FIG. 3, the curve 28 is the function curve of VG-VDD, and the straight line 29 is the load complementary inverter consisting of both transistors of 23.24 and its successor (transition voltage M of the complementary inverter.★-VDDai, Area 30 LtV
G>Va'', area 31 VG<V. ★, vDD★ are the points where VG=VG★. Figure 6 shows the mounting in series when the variable resistor R is made monolithically within the IC. Connection diagram. A is A in Figures 1, 3 and 4.
Same as point. The 0 point is the O level or +VTx level. Figure 7 is a parallel connection diagram when the external variable resistor R is made monolithically within the IC. Both A and C are the same as in Fig. 6.

Claims (1)

[Scope of utility model registration request] In a voltage detection circuit including a voltage level converter and a voltage comparator, the voltage level converter has a first voltage level converter to which a voltage depending on the voltage to be detected is applied between the gate and the source.
A voltage to be detected is applied to both ends of a series circuit including a field effect transistor and a resistor connected to the drain of the field effect transistor, and the voltage comparator is connected to the first field effect transistor. 2nd with opposite polarity
A series circuit of a field effect transistor and a third field effect transistor having the same polarity as the first field effect transistor is connected between the power supply voltages, and the gate of the second field effect transistor is The voltage comparator is connected to the drain of the first field effect transistor or the resistor, the gate of the third field effect transistor is connected to the gate and electrode of the first field effect transistor, and the voltage comparator is connected to the drain of the first field effect transistor or the resistor. A voltage detection circuit that compensates for temperature characteristics of the voltage level converter.