ST52T400 View Datasheet(PDF) - STMicroelectronics

Part Name

Description

Manufacturer

ST52T400

8-BIT INTELLIGENT CONTROLLER UNIT (ICU) Timer/PWM, Analog Comparator, Triac/PWM Timer, WDG

STMicroelectronics 

ST52T400/T440/E440/T441

10 TRIAC/PWM DRIVER

ST52x400/440/441 offers a peripheral able to

generate a TROUT signal on PA0 pin (able to sup-

ply up to 25 mA), to drive an external device, like a

TRIAC, an IGBT or a Power MOS. A Triac/PWM

driver can perform 3 different working modes

according to REG_CONF10(3:2) bits, MODE (see

Table 10.3):

MODE = “00”:

PWM

MODE = “01":

Burst Mode Triac Control

(Thermal Regulations)

MODE = “1x":

Phase Angle Partialization

Triac Control (Motor Control)

The Triac/PWM Driver can be initialized by using a

value fixed by a control algorithm, and stored in

the Register File. The value is loaded in the

TRIAC_COUNT register (Output Register 9) by

using the LDPR instruction and it can be read by

using the LDRI instruction addressing the Input

Register 17.

Figure 10.1 illustrates the internal structure of the

Triac/PWM Driver.

PWM Mode

The PWM working mode selection can be

obtained by setting REG_CONF10(3:2) bits,

MODE, at “00" value.

In this working mode, the peripheral provides a

signal with a fixed period and a variable duty cycle

on the TROUT pin.

The PWM period can be generated starting from

the internal master clock or an external clock sig-

nal applied in MAIN1 pin.

In both cases, the clock signal is divided by a 16-

bit Prescaler, managed by REG_CONF8 and

REG_CONF9 (Figure 10.2).

At each period, the duty cycle is fixed by an 8-bit

value loaded in the TRIAC_COUNT register (Out-

put Register 9). The duty cycle is proportional to

the value: loading 50% duty cycle is obtained,

loading 0 the output will be low (off) during all the

period, loading 255 will be high (on).

By Using a 20 Mhz clock PWM frequencies in the

range between 1.2 Hz to 78.4 Mhz may be

obtained.

Figure 10.1 TRIAC/PWM Driver Block Diagram

REG_CONF8

REG_CONF9

MCLK

EXTCLK

50/60 Hz

MAIN1

MAIN2

MCLK

REG_PERIPH_9

8

TRIAC/PWM DRIVER

PRESCALER

16 bit

CORE

Tck

16

PROGRAMMABLE

COUNTER

PRECLK

MODE

START

RESET

÷2

PULSE

GENERATOR

POL

TRIACOUT

01 2 345 67

REG_CONF10

Tck

63/94

Share Link: