Applicationt:
We are Dandong Hua'ao Electronics Co., Ltd. (China). We specialize in the production of integrated circuits and transistors for automobile and motorcycle. Please note, we are the manufacturer, having own IC production lines, being able to provide the best price.
Production Description:
Rear Window Heating Timer/Long-term Timer ICs
Description
The bipolar long-term timer LD6046/LD6047 (analog U6046B/U6047B)is designed to automatically limit the operation time of high loads in the harsh automotive enviroment with a preset delay time. With the power-on-reset function the timers guarantee that current consuming devices are not operated unintentionally.
The delay time can be interrupted manually, but a retrigger function is not provided.
Features
Delay Time Range: 3.7 s to 20 h
RC Oscillator Determines Timing Characteristics
Relay Driver with Z-diode
Debounced Input for Toggle Switch
Two Debounced Inputs: ON and OFF
Load-dump Protection
RF Interference Protected
LD6046: Inputs Switched to VBatt
LD6047: Inputs Switched to ground
Application instruction of LD6046
1.The controlling input signal
LD6046 has three input signals concluding ON, OFF and TOGGLE. Only when the connecting time t3 of all the controlling input signals is longer than the value according in table1 listed in the Technical Detalis of LD6046, it can make output port (pin2) activation, ensure the relay to be realible action and make a process into normal working condition.
(For example, according to table 1, when C2=100nF, R2=130kΩ, the connecting time must be t3>60ms)
2.The range of operating voltage
Under the working condition that the series resistance of 510Ω is connected in the port of supply voltage (pin8), the Technical Detalis of LD6046 states that the range of operating voltage is 7.0V~16V. However, in the practical circuit, we need to conside the two other factors that can affect the range of operating voltage.
(1) The starting voltage of the normal relay (12V) is about 7.2V.
(2)The saturation voltage drop of the controlling output port of relay (pin2) is V2=1.2V (I2=200mA).
If we add these two voltages, the lowest operating voltage in the practical circuit is 7.2V+1.2V=8.4V. This is consistent with 9V ~ 16V automotive electrical voltage range of standard applications.
3.Interference and surge immunity protection
As for improving the capability of interference and urge immunity protection, you can consider the external series resistance of 510Ω that connected to the port of supply voltage (pin8) , adjusted to 1kΩ. But at the same time, you should pay attention that the range of operating voltage will rise 0.8V.
4.The series resistance of controlling input signal
Please pay particular attention in the Technical Detalis of LD6046, the series resistance of the three controlling input signals is all 7.5kΩ, which is different from 6046 of other companies, their series resistance is 20kΩ. The reason why we choose this application is that we mainly to solve the low voltage range (7V) to use, but does not affect the high voltage (16V) to use.