L6480 datasheet(32/73 Pages) STMICROELECTRONICS

32 / 73 page

Functional description

L6480

32/73

Doc ID 023278 Rev 3

The gate current can be set to one of the following values: 4, 8, 16, 24, 32, 64 and 96 mA

through the IGATE parameter in the GATECFG1 register (see Section 9.1.21).

Controlled current time can be programmed within range from 125 ns to 3.75

μs with a

resolution of 125 ns (TCC parameter in GATECFG1 register) (see Section 9.1.21).

Turn-off overboost time can be set to one of the following values: 0, 62.5, 125, 250 ns

(TBOOST parameter in GATECFG1 register). The 62.5 ns value is only available when clock

frequency is 16 MHz or 32 MHz; when clock frequency is 8 MHz it is changed to 125 ns and

when a 24-MHz clock is used it is changed to 83.3 ns. (see Section 9.1.21).

6.16

Deadtime and blanking time

During the bridge commutation, a deadtime is added in order to avoid cross conductions.

The deadtime can be programmed within a range from 125 ns to 4

μs with a resolution of

125 ns (TDT parameter in the GATECFG2 register) (see Section 9.1.22).

At the end of each commutation the overcurrent and stall detection comparators are

disabled (blanking) in order to avoid the respective systems detecting body diodes turn-off

current peaks.

The duration of blanking time is programmable through the TBLANK parameter in the

GATECFG2 register at one of the following values: 125, 250, 375, 500, 625, 750, 875, 1000

ns (see Section 9.1.22).

6.17

Integrated analog to digital converter

The L6480 integrates an NADC bit ramp-compare analog to digital converter with a reference

voltage equal to VREG. The analog to digital converter input is available through the ADCIN

pin and the conversion result is available in the ADC_OUT register (Section 9.1.16).

Sampling frequency is equal to the programmed PWM frequency.

Figure 14.

Gate driving currents

L6480 データシート(PDF) 32 Page - STMicroelectronics