5v Low Drop Voltage Regulator Ic Ld4275 To263-5 Application: Electrical Industry

Description
The LD4275 is a monolithic integrated low-drop voltage regulator in a 5 pin TO-package. An input voltage up to 45 V is regulated to VQ,nom = 5.0 V. The IC is able to drive loads up to 450 mA and is short-circuit proof. At over temperature the LD4275 is turned off by the incorporated temperature protection. A reset
signal is generated for an output voltage VQ,rt of typ. 4.65 V. The delay time can be programmed by the.external delay capacitor.

Features
a Output voltage 5 V A 2%
a Very low current consumption
a Power-on and undervoltage reset
a Reset low down to VQ = 1 V
a Very low-drop voltage
a Short-circuit-proof
a Reverse polarity proof
a Suitable for use in automotive electronics
a ESD protection > 4 kV

Dimensioning Information on External Components
The input capacitor CI is necessary for compensation of line influences. Using a resistor of approx. 1a in series with CI, the oscillating of input inductivity and input capacitance can be damped. The output capacitor CQ is necessary for the stability of the regulation circuit. Stability is guaranteed at values CQ a Y
22 AuF and an ESR of a 5a within the operating temperature range.


Circuit Description
The control amplifier compares a reference voltage to a voltage that is proportional to the output voltage and drives the base of the series transistor via a buffer. Saturation control as a function of the load current prevents any over saturation of the power element. The IC also incorporates a number of internal circuits for protection against:
a Overload
a Over-temperature
a Reverse polarity