STEVAL-CBL004V1 STMicroelectronics, STEVAL-CBL004V1 Datasheet - Page 7

• Manufacturer Part Number: STEVAL-CBL004V1
• Description: BOARD DEMONSTRATION LNBH PS
• Manufacturer: STMicroelectronics

Specifications of STEVAL-CBL004V1

• Main Purpose: Special Purpose DC/DC, LNB
• Board Type: Fully Populated
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Voltage - Output: -
• Voltage - Input: -
• Power - Output: -
• Utilized Ic / Part: -
• Frequency - Switching: -
• Outputs And Type: -
• Regulator Topology: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

LNBH24L
2.9
2.10
2.11
Note:
failure detected), set to LOW. The diagnostic bits are dedicated to the over-temperature and
over-load protections status (OTF and OLF).
Over-current and short circuit protection and diagnostic
In order to reduce the total power dissipation during an overload or a short circuit condition,
the device is provided with a dynamic short circuit protection. It is possible to set the short
circuit current protection either statically (simple current clamp) or dynamically by the PCL
bit of the I²C SR. When the PCL (pulsed current limiting) bit is set lo LOW, the over current
protection circuit works dynamically: as soon as an overload is detected, the output is shut-
down for a time T
system register is set to "1". After this time has elapsed, the output is resumed for a time
T
protection circuit will cycle again through T
overload is detected, normal operation is resumed and the OLF diagnostic bit is reset to
LOW. Typical T
operation can greatly reduce the power dissipation in short circuit condition, still ensuring
excellent power-on start-up in most conditions. However, there could be some cases in
which a highly capacitive load on the output may cause a difficult start-up when the dynamic
protection is chosen. This can be solved by initiating any power start-up in static mode
(PCL=1) and, then, switching to the dynamic mode (PCL=0) after a chosen amount of time
depending on the output capacitance. When in static mode, the diagnostic OLF bit goes to
"1" when the current clamp limit is reached and returns LOW when the overload condition is
cleared.
Thermal protection and diagnostic
The LNBH24L is also protected against overheating: when the junction temperature
exceeds 150°C (typ.), the step-up converter and the liner regulator are shut-off, and the
diagnostic OTF SR bit is set to "1". Normal operation is resumed and the OTF bit is reset to
LOW when the junction is cooled down to 135°C (typ.)
Output current limit selection
The linear regulator current limit threshold can be set by an external resistor connected to
ISEL pin. The resistor value defines the output current limit by the equation:
Equation 1
where R
application circuit). The highest selectable current limit threshold is 0.9 A typ. with R
k Ω . The above equation defines the typical threshold value for each output. However, it is
suggestible to not exceed for a long period a total amount of current of 1 A from both
sections (I
External components are needed to comply to bidirectional DiSEqC™ bus hardware
requirements. Full compliance of the whole application with DiSEqC™ specifications is not
implied by the bare use of this IC. NOTICE: DiSEqC™ is a trademark of EUTELSAT.
ON
= 1/10 T
SEL
OUT_A
is the resistor connected between I
OFF
ON
+ I
= 90 ms (typ.). At the end of T
OFF
+ T
OUT_B
, typically 900 ms. Simultaneously the diagnostic OLF I²C bit of the
OFF
time is 990 ms and an internal timer determines it. This dynamic
< 1 A) in order to avoid the over temperature protection triggering.
Doc ID 16857 Rev 2
I
I
MAX
MAX
[A]
[A]
OFF
=
=
and T
ON
SEL
10000
10000
R
R
, if the overload is still detected, the
SEL
SEL
and GND (see R2 in the typical
ON
. At the end of a full T
ON
Introduction
in which no
SEL
= 11
7/25