UM2027
STEVAL-IHT008V1
power supplies and typical
consumption
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STEVAL-IHT008V1 power supplies and typical
consumption
Table 2: "Typical STEVAL-IHT008V1 control-circuit consumption"
gives the typical current
consumed from the 5V_DC output for the different operating modes of the STEVAL-
IHT008V1 board.
Table 2: Typical STEVAL-IHT008V1 control-circuit consumption
Operating mode
Current sunk from 5V_DC (mA)
MCU in standby mode
2
MCU running with 1 ACS switch ON (T2 to T5)
14
MCU running with T_ICL ON
17
MCU running with T_ICL and 1 ACS switch ON
24
MCU running with T_ICL and 4 ACS switches ON
45
As listed in
Section 1.2: "Principal board blocks"
, the Flyback implements four output
supplies. The non-regulated 5 V VCC_AC negative supply is used for the Triac and ACS
control. The 15 V and 5 V positive supplies (15V_DC and 5V_DC outputs) are used to
supply circuits referenced to the DC bus Ground (MCU, IPM if one is added).
The 5 V insulated supply (VCC_INS / GND_INS) can be used for sensors if needed. On
original STEVAL-IHT008V1 manufactured boards, this insulated supply is not used.
Only the 15 V positive output is regulated by the VIPer26LD circuit as this supply is always
loaded when the other outputs are loaded. The two 5 V positive supplies (5V_DC,
VCC_INS) are also regulated thanks to two LM2931 positive voltage regulators.
The VCC_AC level is not regulated. Its voltage level will be higher if it is not loaded and if
the 15 V positive supply is loaded with its highest maximum current.
The current capabilities of the different outputs are (for the whole operating range):
for 5V_DC: 90 mA
for VCC_AC (non-regulated 5 V negative output): 200 mA
for 15V_DC: 500 mA (with 5V_DC consumption included)
for VCC_INS (optional 5 V regulated output): 90 mA
Figure 13: "Typical output characteristics of the 5 V negative supply (VCC_AC) and 5 V
insulated supply (VCC_INS)"
and
Figure 14: "Inrush current during STEVAL-IHT008V1
startup on 230 V line (500 µF output DC capacitor)"
give the typical output voltage for the
current which is sunk from each output. These measurements are performed with the
STEVAL-IHT008V1 connected to either a 230 V or 120 V line, with the bridge operating in
rectifier mode (not doubler) and across the entire operating temperature range (0-60 °C).
The 15 V_DC, and the 5 V outputs (5V_DC and VCC_INS) are well regulated thanks to the
VIPer26LD and the LM2931 devices, respectively.
For the VCC_AC, two curves are given to give the minimum and maximum values of this
output. The minimum voltage is reached when the SMPS is delivering the minimum output
current (no current sunk from the 15V_DC and the VCC_INS outputs; the 5V_DC is only
loaded by the MCU, which is controlling one ACS ON).
The VCC_AC measurement is also performed when only one ACS switch is ON as
VCC_AC is dedicated to the Triac and ACS switches driving. So the minimum available
voltage (to define the gate resistor value to apply enough gate current) is an important
value, at least when one AC switch is on.
