Features; Pin Description; Mc34063; Description - Hitachi 42PD3200A Service Manual

cases, the power dissipated is so low that no heatsink is required or its size could be reduced
dramatically.
A standard series of inductors optimized for use with the LM2576 are available from several different
manufacturers. This feature greatly simplifies the design of switch–mode power supplies.
The LM2576 features include a guaranteed ±4% tolerance on output voltage within specified input
voltages and output load conditions, and ±10% on the oscillator frequency (±2% over 0°C to 125°C).
External shutdown is included, featuring 80 mA (typical) standby current. The output switch includes
cycle–by–cycle current limiting, as well as thermal shutdown for full protection under fault conditions.

12.25.2. Features

• 3.3 V, 5.0 V, 12 V, 15 V, and Adjustable Output Versions
• Adjustable Version Output Voltage Range, 1.23 to 37 V ±4% Maximum Over Line and Load
Conditions
• Guaranteed 3.0 A Output Current
• Wide Input Voltage Range
• Requires Only 4 External Components
• 52 kHz Fixed Frequency Internal Oscillator
• TTL Shutdown Capability, Low Power Standby Mode
• High Efficiency
• Uses Readily Available Standard Inductors
• Thermal Shutdown and Current Limit Protection
• Moisture Sensitivity Level (MSL) Equals 1

12.25.3. Pin description

12.26. MC34063

12.26.1. Description

The MC34063A Series is a monolithic control circuit containing the primary functions required for DC–
to–DC converters. These devices consist of an internal temperature compensated reference,
comparator, controlled duty cycle oscillator with an active current limit circuit, driver and high current
output switch. This series was specifically designed to be incorporated in Step–Down and Step–Up and
Voltage–Inverting applications with a minimum number of external components.
12.26.2. Features
• Operation from 3.0 V to 40 V Input
• Low Standby Current
• Current Limiting
• Output Switch Current to 1.5 A
• Output Voltage Adjustable
• Frequency Operation to 100 kHz
• Precision 2% Reference
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