ST HTSSOP38, Manual

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Functional description L6482
32/73 Doc ID 023768 Rev 1
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 9.1.18 ).
Controlled current time can be programmed within range from 125 ns to 3.75
μ
s with a
resolution of 125 ns (TCC parameter in the GATECFG1 register) (see Section 9.1.18 ).
Turn-off overboost time can be set to one of the following values: 0, 62.5, 125, 250 ns
(TBOOST parameter in the 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 9.1.18 ).
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
μ
s with a resolution of
125 ns (TDT parameter in the GATECFG2 register) (see Section 9.1.19 ).
At the end of each commutation the overcurrent and stall detection comparators are
disabled (blanking) in order to avoid the respective systems detecting body diode 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 9.1.19 ).
6.17 Integrated analog-to-digital converter
The L6482 integrates an N
ADC
bit ramp-compare analog-to-digital converter with a
reference voltage equal to
V
REG
. The analog-to-digital converter input is available through
the ADCIN pin and the conversion result is available in the ADC_OUT register
(
Section 9.1.14 ).
The ADC_OUT value can be used for torque regulation or can be at the user’s disposal.
Figure 15. Gate driving currents
G a te C u rrent
G a te t u rn-on
I
g a te
I
g a te
I
OB
t
CC
t
OB
t
CC
G a te ch a rged
G a te di s ch a rged
G a te t u rn-off
AM15045v1