Thursday, June 19, 2014

PWM Controller Circuit using SN75603 and SN75604


Here the circuit diagram of PWM Controller which uses complementary half-H peripheral drivers SN75603 and SN75604, with totem-pole outputs rated at 40 V and 2.0 A. These drivers effectively place the motor in a full-bridge configuration, which has the ability to provide bidirectional control.

USB Cellphone Charger


This is the schematic diagram of cellphone charger circuit which connecter to the USB as main power. Whit this circuit, you can charger your cell phone from USB port in your PC or notebook.

The majority of the cellphones battery is appraised 3.6 volts at 1000 to 1300 mah. These battery packs have 3 Nimh or Lithium cells having 1.2 volt rating. Generally the battery pack requires 4.5 volts and 300-500 mA current for quick charging. Anyway, low present charging is better to build the proficiency of the battery. The circuit depicted here gives 4.7 directed voltage and sufficient present for the moderate charging of the cellphone.

Sunday, July 29, 2012

1.3-12V Small Variable Power Supply


This is a small variable power supply delivers adjustable output voltage of 1.3v-12v. The current output determined by R3. With current setting (see part list), it will deliver current output about 1A.