双单稳态精度 Dual Precision Monostable
General Description
The CD4538BC is a dual, precision monostable multivibrator with independent trigger and reset controls. The device is retriggerable and resettable, and the control inputs are internally latched. Two trigger inputs are provided to allow either rising or falling edge triggering. The reset inputs are active LOW and prevent triggering while active. Precise control of output pulse-width has been achieved using linear CMOS techniques. The pulse duration and accuracy are determined by external components RX and CX. The device does not allow the timing capacitor to discharge
through the timing pin on power-down condition. For this reason, no external protection resistor is required in series with the timing pin. Input protection from static discharge is provided on all pins.
Features
■Wide supply voltage range: 3.0V to 15V
■High noise immunity: 0.45 VCCtyp.
■Low power TTL compatibility: Fan out of 2 driving 74L or 1 driving 74LS
■New formula: PWOUT =RC PW in seconds, R in Ohms, C in Farads
■±1.0% pulse-width variation from part to part typ.
■Wide pulse-width range: 1 µs to ∞
■Separate latched reset inputs
■Symmetrical output sink and source capability
■Low standby current: 5 nA typ. @ 5 VDC
■Pin compatible to CD4528BC