STEVAL-ISA026V1 STMicroelectronics, STEVAL-ISA026V1 Datasheet - Page 12

• Manufacturer Part Number: STEVAL-ISA026V1
• Description: EVAL BOARD 20A 250KHZ L6732
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of STEVAL-ISA026V1

• Design Resources: STEVAL-ISA026V1 Gerber Files STEVAL-ISA026V1 Schematic STEVAL-ISA026V1 Bill of Material
• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 3.3V
• Current - Output: 20A
• Voltage - Input: 4.5 ~ 14V
• Regulator Topology: Buck
• Frequency - Switching: 250kHz
• Board Type: Fully Populated
• Utilized Ic / Part: L6732
• Input Voltage: 4.5 V to 14 V
• Output Voltage: 3.3 V
• Product: Power Management Modules
• Silicon Manufacturer: ST Micro
• Silicon Core Number: L6732
• Kit Application Type: Power Management - Voltage Regulator
• Rohs Compliant: No
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: L6732
• Other names: 497-5869

Device description
5.3
5.4
12/37
Bypassing the LDO to avoid the voltage drop with low Vcc
If V
maximum LDO output current is about 100 mA and so the output voltage drop is 100 mV, to
avoid this the LDO can be by passed.
Figure 4.
Internal and external references
It is possible to set the internal/external reference and the switching frequency by setting the
proper voltage at the EAREF pin. The maximum value of the external reference depends on
the V
5V the maximum external reference is 2.5 V (typ.).
Providing an external reference from 0 V to 450 mV the output voltage will be regulated but
some restrictions must be considered:
To set the resistor divider it must be considered that a 100 k pull-down resistor is integrated
into the device (see
EAREF pin is captured by the device at the start-up when V
CC
CC
≈
: with V
5 V the internal LDO works in dropout with an output resistance of about 1 Ω. The
●
●
●
●
●
●
Bypassing the LDO
V
V
V
OV threshold saturates to a minimum value of 300 mV (OV is tracking the
reference; tracking small references will result in a narrow threshold reducing
noise immunity)
The under-voltage-protection doesn't work;
The PGOOD signal remains low;
CC
EAREF
EAREF
EAREF
= 4 V the clamp operates at about 2 V (typ.), while with V
Figure
from 0 % to 80 % of V
from 80 % to 95 % of V
from 95 % to 100 % of V
5.). Finally it must be taken into account that the voltage at the
CCDR
CCDR
CCDR
-> External reference/Fsw = 250 kHz
-> V
-> V
REF
REF
CC
= 0.6V/Fsw = 500 kHz
= 0.6V/Fsw = 250 kHz
is about 4 V.
CC
greater than
L6732