HT8A977B Datasheet | HOTCHIP

Description The HT8A977B and HT8A978B provide plete control functions to the remote-controlled toy. The HT8A977B has five input pins corresponding with the five function buttons i.e, forward, backward, rightward, leftward and turbo. The encoding circuit in the HT8A977B sends digital codes to the two output pins SO and SC. The digital codes correspond to the definite function buttons or their binations. The SO and SC outputs are used in wireless and infra-red applications respectively. The HT8A978B has five output pins corresponding with the five actions. The received signals are amplified by the three-stage amplifier, and then the appropriate amplified signals are sampled, fault-tolerantly checked and decoded to control the actions of the remote-controlled toy. There is an internal oscillator in the HT8A977B and 978B respectively. By adding an external resistor conveniently, the oscillator will be constructed. The oscillator frequency can be adjusted by the external resistor. The relative error between the frequencies of the two on-chip oscillators in the HT8A977B and HT8A978B must be less than ±25%. The auto-power-off function is achieved by an internal counter (977B). The PC output is used to control on/off state of the external power supply. Press on any function button will wake up the chip promptly. FEATURES - HT8A977B works as encoder and HT8A978B works as decoder - Five pins for five control functions - Operating power-supply voltage: 2.5V to 5.0V (978B), 1.8V to 5.0V(977B) - Auto-power-off and oscillation-off if no press on any button (977B) - Press on any button to wake up (977B) - One output pin used for external power control (977B) - On-chip oscillator with an external resistor - On-chip reversing amplifiers (978B) - Low operating current - Few external ponents needed - Package: 14-pin DIP, 14-pin SOIC, 16-pin DIP, 16-pin SOIC, die form and wafer form Ordering Information Part No. Package HT8A977BPE Lead free 14-pin DIP HT8A977BWE Lead free...