Kannan N is the chief executive officer of Mediatronix Pvt. Ltd., Trivandrum, Kerala, India. He holds a B-Tech in electronics and communication from the College of Engineering, Trivandrum. Email address: kannan@mtxglobal.com
3 results found for Kannan N, displaying items 1 - 3
July 5, 2007[Ideas For Design] Sequence Generator Delays Bias Voltages To LCDs
Many graphic (passive/active (TFT)) LCDs require multiple positive and negative supply voltages. At “power on” and “power off,” these bias voltages must be sequenced properly, along with the LCD’s data and control signals, to prevent damage to the LCDs. Figure 1 shows a circuit that can provide the needed sequencing. The inverters are 74HC14 Schmitt types. The resistor-diode-capacitor...
November 6, 2006[Ideas For Design] Auto-Resetting Circuit Protects Auxiliary Outputs Against Shorts
Many products require an auxiliary dc output to power external devices or subsystems. If such subsystems are to be hot-connected, the auxiliary output must be protected against short circuits. Schemes using fuses are slow and will cause the internal dc-rail to drop, possibly affecting the main system. The circuit shown in the figure provides pulse current limiting at a very low cost. It can handle momentary or...
October 26, 2006[Ideas For Design] Give Your Projects Under- And Overvoltage Protection With Hysteresis
This circuit provides undervoltage and overvoltage protection for dc input supply voltages (see the figure). Its undervoltage cutoff is 6 V, and its overvoltage cutoff is 11.5 V. When VIN is less than about 6 V, Q1 and Q2 are OFF; Q3 (a series MOSFET switch) is also OFF and VOUT = 0. When VIN goes over about 6 V, Q1 turns ON, turning ON the series MOSFET. Then, VOUT =...
