
Fujitsu
■ DESCRIPTION
The MB3821 is a pulse width modulation (PWM) type 2-channel DC/DC converter IC with synchronous rectification designed for low voltage, high efficiency operation in high precision and high frequency applications, ideal for down conversion.
A normal/low-power mode selection is provided, ideal for an internal power supply (3.3V, 5V) in applications with substantial load current variation, such as notebook computers.
■ FEATURES
• Synchronous rectification
• High efficiency : 93 % (normal power mode, VIN = 6 V, load 1 A)
: 84 % (low power mode, VIN = 6 V, load 20 mA)
• Built-in power mode selector circuit
• Reference voltage accuracy : 2.5V ± 2 %
• Built-in error amp input control type soft start circuit
• Totem pole type output for N-ch MOSFET applications
• Built-in timer-latch type short protection circuit