TA7366,67 five-lamp single driver circuit

The commonly used single-channel display drive circuit TA 7366/7367 is a 5-lamp LED drive circuit produced by Toshiba. It
adopts 9-pin single in-line plastic packaging structure. The internal circuit structure and application circuit are shown in Figure 4-48. This circuit Contains 6 operational
amplifiers and 1 reference voltage circuit. One of the 6 operational amplifiers is used as an input amplifier to amplify the input signal to
obtain a sufficient driving level . The remaining 5 constitute 5 groups of voltage comparators. The 5-level voltage comparator
compares . When the input When the signal level is greater than the reference voltage , the comparator outputs a low level, driving the light-emitting diode of this level to emit light.
For TA7366, its fifth light-emitting diode k is 0 level, followed by b is 3 dB, LD is 6 dB,
Lm is iicB, and LDI is 16 dB. For TA7367. LD5 is OdB, k is -2衄, k is -4dB, Lm
is -6dB, and LD1 is -8dB. The difference between the two drive circuits
is: first, the maximum display range: one is 0 to - 16dB, and one is 0 - 8dB; second, the interval level of each segment is different: one has an interval of 3, 3.5, SdB, and one is 0 to - 8dB. Only the intervals are
2dB. The remaining electrical parameters are the same for both, power supply voltage range V∞: 4~12V; quiescent current,∞: 3mA; output current
8rnA; lighting sensitivity V': 230mV (the fifth lamp is on) o