L6726A STMicroelectronics, L6726A Datasheet - Page 13
![IC CTRLR PWM 1PHASE SO-8](/photos/1/38/13851/497-8-soic_sml.jpg)
L6726A
Manufacturer Part Number
L6726A
Description
IC CTRLR PWM 1PHASE SO-8
Manufacturer
STMicroelectronics
Type
Step-Down (Buck)r
Datasheet
1.L6726ATR.pdf
(35 pages)
Specifications of L6726A
Internal Switch(s)
No
Synchronous Rectifier
No
Number Of Outputs
1
Voltage - Output
Adj to 0.8V
Frequency - Switching
270kHz
Voltage - Input
1.5 ~ 12 V
Operating Temperature
-20°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
8-SOIC (3.9mm Width)
Output Current
1.5 A
Input Voltage
4.1 V to 13.2 V
Operating Temperature Range
- 40 C to + 150 C
Mounting Style
SMD/SMT
For Use With
497-9046 - BOARD EVAL BASED ON L6726A497-6364 - BOARD DEMO FOR TS4995EIJT497-6259 - BOARD EVAL 1PH STPDN CONV L6726A
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Current - Output
-
Power - Output
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
L6726A
Manufacturer:
ST
Quantity:
20 000
Part Number:
L6726AD
Manufacturer:
ST
Quantity:
20 000
Company:
Part Number:
L6726ATR
Manufacturer:
FUJI
Quantity:
130
Part Number:
L6726ATR
Manufacturer:
ST
Quantity:
20 000
L6726A
7
7.1
7.1.1
7.2
Protections
Overcurrent protection
The overcurrent feature protects the converter from a shorted output or overload, by sensing
the output current information across the low side MOSFET drain-source on-resistance,
R
expensive and space-consuming sense resistors.
The low side R
node when LS MOSFET is turned on with the programmed OCP threshold voltage,
internally held. If the monitored voltage drop (GND to PHASE) exceeds this threshold, an
Overcurrent event is detected. If two overcurrent events are detected in two consecutive
switching cycles, the protection will be triggered and the device will turn off both LS and HS
MOSFETs in a latched condition.
To recover from over current protection triggered, VCC power supply must be cycled.
Overcurrent threshold setting
L6726A allows to easily program an overcurrent threshold ranging from 50 mV to 550 mV,
simply by adding a resistor (R
During a short time following VCC rising over UVLO threshold, an internal 10µA current
(I
voltage drop will be sampled and internally held by the device as overcurrent Threshold. The
OC setting procedure overall time length ranges from 5.5 ms to 6.5 ms, proportionally to the
threshold being set.
Connecting a R
R
If the voltage drop across R
inrush current and noise. This can result in undesired OCP triggering. In this case, consider
increasing R
In case R
default value: an internal safety clamp on LGATE is triggered as soon as LGATE voltage
reaches 700 mV (typ), enabling the 400 mV default threshold and suddenly ending OC
setting phase.
See
waveforms.
Feedback disconnection protection
In order to provide load protection even if FB pin is not connected, a 100 nA bias current is
always sourced from this pin. If FB pin is not connected, bias current will permanently pull
up FB: this forces COMP pin low, avoiding output voltage rising to dangerous levels.
OCSET
dsON
OCSET
Figure 6
. This method reduces cost and enhances converter efficiency by avoiding the use of
) is sourced from LGATE pin, determining a voltage drop across R
I
values range from 5 kΩ to 55 kΩ.
OCth
OCSET
OCSET
for OC threshold setting procedure timings picture and oscilloscope sample
dsON
=
OCSET
is not connected, the device switches the OCP threshold to a 400 mV
I
------------------------------------------- -
OCSET
value.
current sense is implemented by comparing the voltage at the PHASE
resistor between LGATE and GND, the programmed threshold will be:
R
dsON
⋅
OCSET
R
OCSET
Doc ID 12754 Rev 4
OCSET
is too low, the system will be very sensitive to start-up
) between LGATE and GND.
OCSET
Protections
. This
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