L9805E datasheet(32/127 Pages) STMICROELECTRONICS

Part #	L9805E

Description	Super smart power motor driver with 8-Bit MCU, RAM, EEPROM, ADC, WDG, Timers, PWM and H-bridge driver

PDF	127 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

Logo

32 / 127 page

Voltage Regulator

L9805E

32/127

Voltage Regulator

4.1

Introduction

The on chip voltage regulator provides two regulated voltage, nominally 5V both. VCC

supplies ADC and the analog periphery and VDD supplies the microcontroller and logic

parts. These voltage are available at pins VDD and VCC to supply external components and

connects a capacitors to optimize EMI performance. A pre-regulator circuit allows to connect

external tantalum capacitors to a lower (10V) voltage (VB2 pin).

4.1.1

Functional Description

The main supply voltage is taken from VB1 pin. A voltage pre-regulator provides the

regulated voltage on pin VB2. VB2 is the supply for the digital and analog regulators. The

block diagram shows the connections between the regulators and the external pins.

In order to prevent negative spikes on the battery line to propagate on the internal supply

generating spurious reset, a series diode supply VB1 pin is recommended.

Figure 15.

Voltage regulation block diagram

ADC

PRE-REGULATOR

VB1

VB2

force

ANALOG

VOLTAGE

REGULATOR

sense

VCC

AGND

DIGITAL

VOLTAGE

REGULATOR

VDD

GND

Battery

L9805E Datasheet(PDF) 32 Page - STMicroelectronics