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LNBH26
Dual LNBS supply and control IC with step-up and I²C interface
Features
■
Complete interface between LNB and I²C bus
■
Built-in DC-DC converter for single 12 V supply
operation and high efficiency (typ. 93% @
0.5 A)
■
Selectable output current limit by external
resistor
■
Compliant with main satellite receivers output
voltage specification (15 programmable levels)
QFN24 (4 x 4 mm)
■
Accurate built-in 22 kHz tone generator suits
widely accepted standards
■
22 kHz tone waveform integrity guaranteed
also at no load condition
Description
■
Low drop post regulator and high efficiency
step-up PWM with integrated power N-MOS
allowing low power losses
■
LPM function (low power mode) to reduce
dissipation
■
Overload and overtemperature internal
protection with I²C diagnostic bits
■
LNB short-circuit dynamic protection
■
+/- 4 kV ESD tolerant on output power pins
Intended for analog and digital dual satellite
receivers/Sat-TV, and Sat-PC cards, the LNBH26
is a monolithic voltage regulator and interface IC,
assembled in QFN24 4x4 specifically designed to
provide the 13/18 V power supply and the 22 kHz
tone signalling to the LNB down-converter in the
antenna dishes or to the multi-switch box. In this
application field, it offers a complete solution for
dual tuner satellite receivers with extremely low
component count, low power dissipation together
with simple design and I²C standard interfacing.
Applications
■
STB satellite receivers
■
TV satellite receivers
■
PC card satellite receivers
Table 1.
Device summary
Order code
Package
Packaging
LNBH26PQR
QFN24 (4 x 4)
Tape and reel
February 2012
Doc ID 022771 Rev 1
1/38
www.st.com
38
Contents
LNBH26
Contents
1
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2
Application information (valid for each section A/B) . . . . . . . . . . . . . . . 4
2.1
DISEQC™ data encoding (DSQIN pin) . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2
Data encoding by external 22 kHz tone TTL signal . . . . . . . . . . . . . . . . . . 4
2.3
Data encoding by external DiSEqC envelope control
through the DSQIN pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.4
LPM (low power mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.5
DISEQC™ 2.0 implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.6
Output current limit selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.7
Output voltage selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.8
Diagnostic and protection functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.9
Surge protections and TVS diodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.10
FLT: Fault FLAG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.11
VMON: output voltage diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.12
TMON: 22 kHz tone diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.13
TDET: 22 kHz tone detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.14
IMON: minimum output current diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.15
PDO: overcurrent detection on output pull-down stage . . . . . . . . . . . . . . . 8
2.16
Power-on I²C interface reset and undervoltage lockout . . . . . . . . . . . . . . . 8
2.17
PNG: input voltage minimum detection . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.18
ISW: inductor switching current limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.19
COMP: boost capacitor ESR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.20
OLF: overcurrent and short-circuit protection and diagnostic . . . . . . . . . . . 9
2.21
OTF: thermal protection and diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5
Typical application circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6
I²C bus interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2/38
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LNBH26
7
8
Contents
6.1
Data validity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.2
Start and stop condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.3
Byte format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.4
Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.5
Transmission without acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
I²C interface protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.1
Write mode transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.2
Read mode transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
7.3
Data registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
7.4
Status registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
8.1
Output voltage selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
9
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
10
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Doc ID 022771 Rev 1
3/38
Block diagram
1
LNBH26
Block diagram
Figure 1.
Block diagram
DSQIN-A ADDR SCL SDA
DSQIN-B
DAC
Drop control
Tone ctrl
Diagnostics
Protections
Linear
Regulator
PGND
VUP-B
Linear
Regulator
Gate ctrl
Gate ctrl
VUP-A
Tone
detector
Tone
detector
Current
Limit
selection
BPSW-A
Voltage
reference
ISEL GND
4/38
VOUT-B
DETIN-B
DETIN-A
DSQOUT-A
Isense
I²C Digital core
PGND
VOUT-A
PWM CTRL
PWM CTRL
LX-B
Isense
LX-A
BYP VCC
Doc ID 022771 Rev 1
DSQOUT-B
BPSW-B
FLT
AM10475v1
LNBH26
2
Application information (valid for each section A/B)
Application information (valid for each section A/B)
The LNBH26 includes two completely independent sections. Except for ISEL, VCC and I²C
inputs, each circuit can be separately controlled and have their independent external
components. All the specifications below must be considered equal for both sections (A/B).
This IC has a built-in DC-DC step-up converter that, from a single source (8 V to 16 V),
generates the voltages (VUP) that let the integrated LDO post-regulator (generating the 13 V
/ 18 V LNB output voltages plus the 22 kHz DiSEqC™ tone) work with a minimum dissipated
power of 0.5 W typ. @ 500 mA load (the LDO drop voltage is internally kept at VUP - VOUT =
1 V typ.). The LDO power dissipation can be further reduced when 22 kHz tone output is
disabled by setting the LPM bit to “1” (see LPM function description). The IC is also provided
with an undervoltage lockout circuit that disables the whole circuit when the supplied VCC
drops below a fixed threshold (4.7 V typ.). The step-up converter soft-start function reduces
the in-rush current during startup. The SS time is internally fixed at 4 ms typ. to switch from
0 to 13 V, and 6 ms typ. to switch from 0 to 18 V.
2.1
DISEQC™ data encoding (DSQIN pin)
The internal 22 kHz tone generator is factory trimmed in accordance with the DiSEqC™
standards, and can be activated in 3 different ways:
1.
by an external 22 kHz source DiSEqC™ data connected to the DSQIN logic pin (TTL
compatible). In this case the I²C tone control bits must be set: EXTM=TEN=1.
2.
by an external DiSEqC™ data envelope source connected to the DSQIN logic pin. In
this case the I²C tone control bits must be set: EXTM=0 and TEN=1.
3.
through the TEN I²C bit if the 22 kHz presence is requested in continuous mode. In this
case the DSQIN TTL pin must be pulled HIGH and the EXTM bit set to “0”.
Each of the above solutions requires that during the 22 kHz tone activation and/or
DiSEqC™ data transmission, the LPM bit must be set to “0” [see 2.4: LPM (low power
mode)].
2.2
Data encoding by external 22 kHz tone TTL signal
In order to improve design flexibility an external tone signal can be input to the DSQIN pin by
setting the EXTM bit to “1”.
The DSQIN is a logic input pin which activates the 22 kHz tone to the VOUT pin, by using the
LNBH26 integrated tone generator.
The output tone waveforms are internally controlled by the LNBH26 tone generator in terms
of rise/fall time and tone amplitude, while, the external 22 kHz signal on the DSQIN pin is
used to define the frequency and the duty cycle of the output tone. A TTL compatible 22 kHz
signal is required for the proper control of the DSQIN pin function. Before sending the TTL
signal on the DSQIN pin, the EXTM and TEN bits must be previously set to “1”. As soon as
the DSQIN internal circuit detects the 22 kHz TTL external signal code, the LNBH26
activates the 22 kHz tone on the VOUT output with about 1 µs delay from TTL signal
activation, and it stops with about 60 µs delay after the 22 kHz TTL signal on DSQIN has
expired (refer to Figure 2).
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Application information (valid for each section A/B)
Figure 2.
LNBH26
Tone enable and disable timing (using external waveform)
DSQIN
~ 1 µs
~ 60 µs
Tone
Output
AM10426v1
2.3
Data encoding by external DiSEqC envelope control through
the DSQIN pin
If an external DiSEqC™ envelope source is available, it is possible to use the internal 22
kHz generator activated during the tone transmission by connecting the DiSEqC™ envelope
source to the DSQIN pin. In this case the I²C tone control bits must be set: EXTM=0 and
TEN=1. In this way the internal 22 kHz signal is superimposed on the VOUT DC voltage to
generate the LNB output 22 kHz tone. During the period in which the DSQIN is kept HIGH
the internal control circuit activates the 22 kHz tone output.
The 22 kHz tone on the VOUT pin is activated with a delay of about 6 µs from DSQIN TTL
signal rising edge, and it stops with a delay time in the range of 15 µs to 60 µs after the 22
kHz TTL signal on DSQIN has expired (refer to Figure 3).
Figure 3.
Tone enable and disable timing (using envelope signal)
DSQIN
15 µs ~ 60 µs
~ 6 µs
Tone
Output
AM10427v1
2.4
LPM (low power mode)
In order to reduce total power loss, each section of the LNBH26 is provided with the LPM I²C
bit that can be activated (LPM=1) in applications where the 22 kHz tone can be disabled for
long time periods. The LPM bit can be set to “1” when the DiSEqC™ data transmission is
not requested (no 22 kHz tone output is present); in this condition the drop voltage across
the integrated LDO regulator (VUP - VOUT) is reduced to 0.6 V typ. and, consequently, the
power loss inside the relative LNBH26 channel regulator is reduced too. For example, at 500
mA load, LPM=1, allowing a minimum LDO dissipated power of 0.3 W typ. It is
recommended to set the LPM bit to “0” before starting the 22 kHz DiSEqC™ data
transmission; in this condition the drop voltage across the LDO is kept to 1 V typ. Keep
LPM=0 at all times in case the LPM function is not used.
2.5
DISEQC™ 2.0 implementation
The built-in 22 kHz tone detector completes the fully bi-directional DiSEqC™ 2.0 interfacing.
Each LNBH26 section DETIN pin must be AC coupled to the DiSEqC™ bus, and extracted
PWK data is available on the corresponding DSQOUT pin. To comply with the bi-directional
DiSEqC™ 2.0 bus hardware requirements, an output R-L filter is needed (per each voltage
6/38
Doc ID 022771 Rev 1
LNBH26
Application information (valid for each section A/B)
output pin). In order to avoid 22 kHz waveform distortion during tone transmission, each
LNBH26 section is provided with a BPSW pin to be connected to an external transistor,
which allows the bypassing of the corresponding output RL filter in DiSEqC 2.x applications
while in transmission mode. Before starting tone transmission by means of the DSQIN pin,
provide that the TEN bit is preventively set to “1” and after ending tone transmission, provide
that the TEN bit is set to “0”.
2.6
Output current limit selection
The linear regulators current limit threshold can be set by an external resistor connected to
the ISEL pin. The resistor value defines the output current limit by the equation:
Equation 1
IMAX (typ.) =
16578
RSEL1.206
with ISET=0
Equation 2
IMAX (typ.) =
6452
RSEL1.159
with ISET=1
(Refer also to the ISET bit description in Table 9.)
where RSEL is the resistor connected between ISEL and GND expressed in kΩ and
IMAX(typ.) is the typical current limit threshold expressed in mA. IMAX can be set up to 1 A for
each channel. However, it is recommended to not exceed, for a long period, a total amount
of current of 1 A from both sections (IOUT_A + IOUT_B < 1 A) in order to avoid the
overtemperature protection triggering and to thoroughly validate the PCB layout thermal
management in real application environment conditions.
2.7
Output voltage selection
Each linear regulator channel output voltage level can be easily programmed in order to
accomplish application specific requirements, using 4 + 4 bits of an internal DATA1 register
(see Section 7.3: Data registers and Table 14: Output voltage selection table (Data1
register, write mode) for exact programmable values). Register writing is accessible via the
I²C bus.
2.8
Diagnostic and protection functions
The LNBH26 has 14 diagnostic internal functions provided via the I²C bus, by reading 14
bits on two STATUS registers (in read mode). All the diagnostic bits are, in normal operation
(that is, no failure detected), set to LOW. One diagnostic bit is dedicated to the
overtemperature status (OTF), one bit is dedicated to the input voltage power not good
function (PNG), while the remaining 12 bits (6 per channel) are dedicated to the overload
Doc ID 022771 Rev 1
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Application information (valid for each section A/B)
LNBH26
protection status (OLF), to the output voltage level (VMON), to 22 kHz tone characteristics
(TMON), to the minimum load current (IMON), to external voltage source presence on the
VOUT pin (PDO), and to 22 kHz tone presence on the DETIN pin (TDET). Once the OLF (or
the OTF or PNG) bit has been activated (set to “1”), it is latched to “1” until the relevant
cause is removed and a new register reading operation is done.
2.9
Surge protections and TVS diodes
Each LNBH26 device section is directly connected to the antenna cable in a set-top box.
Atmospheric phenomenon can cause high voltage discharges on the antenna cable causing
damage to the attached devices. Surge pulses occur due to direct or indirect lightning
strikes to an external (outdoor) circuit. This leads to currents or electromagnetic fields
causing high voltage or current transients. Transient voltage suppressor (TVS) devices are
usually used, as shown in the following schematic (Figure 4), to protect each section of STB
output circuits where the LNBH26 and other devices are electrically connected to the
antenna cable.
Figure 4.
Surge protection circuit
For this purpose we recommend the use of LNBTVSxx surge protection diodes specifically
designed by ST. The selection of the LNBTVS diode should be made based on the
maximum peak power dissipation that the diode is capable of supporting (see the LNBTVS
datasheet for further details).
2.10
FLT: Fault FLAG
In order to get an immediate feedback on a diagnostic status, the LNBH26 is equipped with
a dedicated fault flag pin (FLT). In the case an overload (OLF bit=1), overheating (OTF bit=1)
or power not good (PNG bit=1) condition is detected, the FLT pin (open drain output) is set
to low and is kept low until the relevant activating diagnostic bit is cleared. Be aware that
diagnostic bits OLF, OTF and PNG, once activated, are kept latched to “1” until the origin
cause is removed and a new register reading operation is performed by the microprocessor.
The FLT pin must be connected to a positive voltage (5 V max.) by means of a pull-up
resistor.
2.11
VMON: output voltage diagnostic
When one device output voltage is activated (VOUT pin), its value is internally monitored
and, as long as the output voltage level is below the guaranteed limits, the relevant VMON
I²C bit is set to “1” (see Table 17 for more details).
8/38
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LNBH26
2.12
Application information (valid for each section A/B)
TMON: 22 kHz tone diagnostic
The 22 kHz tone can be internally detected and monitored if one (or both) DETIN pin are
connected to the LNB output bus (see Figure 7) through a decoupling capacitor.
The tone diagnostic function is provided with the corresponding TMON I²C bit. If the 22 kHz
tone amplitude and/or the tone frequency is out of the guaranteed limits (see Table 19), the
corresponding TMON I²C bit is set to “1”.
2.13
TDET: 22 kHz tone detection
When a 22 kHz tone presence is detected on one DETIN pin, the corresponding TDET I²C
bit is set to “1”.
2.14
IMON: minimum output current diagnostic
In order to detect the output load absence (no LNB connected on the bus or cable not
connected to the IRD) each LNBH26 section is provided with a minimum output current flag
by the corresponding IMON I²C bit, accessible in read mode, which is set to “1” if the output
current is lower than 12 mA (typ.). It is recommended to use the IMON function only with the
22 kHz tone transmission deactivated, otherwise the IMON bit could be set to “0” even if the
output current is below the minimum current threshold. To activate the IMON diagnostic
function, set to “1” the EN_IMON I²C bit in the DATA4 register. Be aware that as soon as the
IMON function is activated by means of EN_IMON=1, the VOUT is immediately increased to
21 V (typ.) independently on the VSEL bit setting. This operation is applied in order to be
sure that the LNBH26 output has the higher voltage present in the LNB bus. Do not use this
function in an application environment where a 21 V voltage level is not supported by other
peripherals connected to the LNB bus.
2.15
PDO: overcurrent detection on output pull-down stage
When an overcurrent occurs on one section pull-down output stage due to an external
voltage source greater than the LNBH26 nominal VOUT, and for a time longer than
ISINK_TIME_OUT (10 ms typ.), the corresponding PDO I²C bit is set to “1”. This may happen
due to an external voltage source presence on the LNB output (VOUT pin).
For current threshold and deglitch time details, see Table 13.
2.16
Power-on I²C interface reset and undervoltage lockout
The I²C interface built into the LNBH26 is automatically reset at power-on. As long as the
VCC stays below the undervoltage lockout (UVLO) threshold (4.7 V typ.), the interface does
not respond to any I²C command and all DATA register bits are initialized to zeroes,
therefore keeping the power blocks disabled. Once the VCC rises above 4.8 V typ., the I²C
interface becomes operative and the DATA registers can be configured by the main
microprocessor.
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Application information (valid for each section A/B)
2.17
LNBH26
PNG: input voltage minimum detection
When input voltage (VCC pin) is lower than LPD (low power diagnostic) minimum thresholds,
the PNG I²C bit is set to “1” and the FLT pin is set low. Refer to Table 3 for threshold details.
2.18
ISW: inductor switching current limit
In order to allow low saturation current inductors to be used, the maximum DC-DC inductor
switching current limit threshold can be set by means of one I²C bit per section (ISW). Two
values are available: 2.5 A typ. (with ISW = 1) and 4 A typ. (with ISW = 0).
2.19
COMP: boost capacitor ESR
The DC-DC converter compensation loop can be optimized in order to work well with high or
low ESR capacitors (on the VUP pin). For this purpose, one I²C bit in the DATA4 register
(COMP) can be set to “1” or “0”. It is recommended to reset this bit to “0” unless using high
ESR capacitors.
2.20
OLF: overcurrent and short-circuit protection and diagnostic
In order to reduce the total power dissipation during an overload or a short-circuit condition,
each section of 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 corresponding PCL bit of the I²C DATA3 register. When the PCL (pulsed current
limiting) bit is set lo LOW, the overcurrent protection circuit works dynamically: as soon as
an overload is detected, the output current is provided for TON time (90 ms or 180 ms typ.,
according to the corresponding TIMER bit programmed in the DATA3 register) and after that,
the output is set in shutdown for a TOFF time of typically 900 ms. Simultaneously, the
corresponding diagnostic OLF I²C bit of the STATUS1 register is set to “1” and the FLT pin is
set to low level. After this time has elapsed, the involved output is resumed for a time TON. At
the end of TON, if the overload is still detected, the protection circuit cycles again through
TOFF and TON. At the end of a full TON in which no overload is detected, normal operation is
resumed and the OLF diagnostic bit is reset to LOW after register reading is done. Typical
TON +TOFF time is 990 ms (if TIMER=0) or 1080 ms (if TIMER=1) and is determined by an
internal timer. This dynamic operation can greatly reduce the power dissipation in shortcircuit condition, still ensuring excellent power-on startup in most conditions. However, there
may be some cases in which a highly capacitive load on the output can cause a difficult
startup when the dynamic protection is chosen. This can be solved by initiating any power
startup in static mode (PCL=1) and then, switching to dynamic mode (PCL=0) after a
chosen amount of time, depending on the output capacitance. Also in static mode, the
diagnostic OLF bit goes to “1” (and the FLT pin is set to low) when the current clamp limit is
reached and returns LOW when the overload condition is cleared and register reading is
done.
After the overload condition is removed, normal operation can be resumed in two ways,
according to the OLR I²C bit on the DATA4 register.
If OLR=1, all VSEL bits corresponding to the involved section are reset to “0” and the LNB
section output (VOUT pin) is disabled. To re-enable the output stage, the VSEL bits must be
set again by the microprocessor and the OLF bit is reset to “0” after a register reading
operation.
10/38
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LNBH26
Application information (valid for each section A/B)
If OLR=0, the involved output is automatically re-enabled as soon as the overload condition
is removed, and the OLF bit is reset to “0” after a register reading operation.
2.21
OTF: thermal protection and diagnostic
The LNBH26 is also protected against overheating: when the junction temperature exceeds
150 °C (typ.), the step-up converter and both liner regulators are shut off, the diagnostic
OTF bit in the STATUS1 register is set to “1” and the FLT pin is set to low level. After the
overtemperature condition is removed, normal operation can be resumed in two ways,
according to the THERM I²C bit on the DATA4 register.
If THERM=1, all VSEL bits are reset to “0” and both LNB outputs (VOUT pins) are disabled.
To re-enable output stages, the VSEL bits must be set again by the microprocessor, while
the OTF bit is reset to “0” after a register reading operation.
If THERM=0, outputs are automatically re-enabled as soon as the overtemperature
condition is removed, while the OTF bit is reset to “0” after a register reading operation.
Doc ID 022771 Rev 1
11/38
Pin configuration
3
LNBH26
Pin configuration
Figure 5.
Table 2.
Pin connections (top view)
24
23
22
21
20
19
DSQIN - B
DSQOUT - A
DSQIN -A
-
VUP -A
VOUT -A
-
DETIN -A
-
1
DSQOUT -B
-
BPSW -A
-
18
2
FLT
VCC
17
3
LX -A
BYP
16
4
PGND
GND
15
5
LX -B
-
NC
14
6
ADDR
BPSW -B
13
SCL
SDA
ISEL
VUP - B
VOUT - B
DETIN -B
7
8
9
10
11
12
AM10476v1
Pin description
Pin
Symbol
Name
Pin function
1
DSQOUT-B
DiSEqC output
Open drain output of channel A tone detector to the main microcontroller
for DiSEqC 2.0 data decoding. It is low when tone is detected on the
DETIN-B input pin. Set to ground if not used.
2
FLT
FLT
Open drain output for IC fault conditions. It is set low in case of overload
(OLF bit) or overheating status (OTF bit) or power not good (PNG bit) is
detected. To be connected to pull-up resistor (5 V max.).
3
LX-A
N-Mos drain
4
P-GND
Power ground
5
LX-B
N-Mos drain
6
ADDR
Address setting
7
SCL
Serial clock
Clock from I²C bus.
8
SDA
Serial data
Bi-directional data from/to I²C bus.
9
12/38
ISEL
Channel A, integrated N-channel Power MOSFET drain.
DC-DC converter power ground. To be connected directly to the exposed
pad.
Channel B, integrated N-channel Power MOSFET drain.
Two I2C bus addresses available by setting the address pin level voltage.
See Table 16.
The resistor “RSEL” connected between ISEL and GND defines the linear
Current selection
regulator current limit threshold. Refer to Section 2.5. Also see the ISET
for both channel
bit description in Table 9. The RSEL resistor defines the same current
A and B
limit both for channels A and B.
Doc ID 022771 Rev 1
LNBH26
Table 2.
Pin configuration
Pin description (continued)
Pin
Symbol
Name
Pin function
10
VUP-B
Channel B
step-up voltage
Input of channel B linear post-regulator. The voltage on this pin is
monitored by the internal channel B step-up controller to keep a minimum
dropout across the linear pass transistor.
11
VOUT-B
Channel B,
LNB output port
Output of channel B integrated very low drop linear regulator. See
Table 14 for voltage selection and description.
12
DETIN-B
Tone detector
input
Channel B, 22 kHz tone decoder input, must be AC coupled to the
DiSEqC 2.0 bus. Set to ground if not used.
13
BPSW-B
Switch control
To be connected to an external transistor to be used to bypass the
channel B output RL filter needed in DiSEqC 2.x applications during the
DiSEqC transmitting mode (see Section 5). Set to ground if not used.
Open drain pin.
14
N.C.
Not internally
connected
Not internally connected pin. Set floating if not used.
15
GND
Analog ground
16
BYP
17
VCC
Analog circuits ground. To be connected directly to the exposed pad.
Needed for internal pre-regulator filtering. The BYP pin is intended only to
connect an external ceramic capacitor. Any connection of this pin to
Bypass capacitor
external current or voltage sources may cause permanent damage to the
device.
Supply input
8 to 16 V IC DC-DC power supply.
18
BPSW-A
Switch control
To be connected to an external transistor to be used to bypass the
channel A output RL filter needed in DiSEqC 2.x applications during the
DiSEqC transmitting mode (see Section 5). Set to ground if not used.
Open drain pin.
19
DETIN-A
Tone detector
input
Channel A, 22 kHz tone decoder input, must be AC coupled to the
DiSEqC 2.0 bus. Set to ground if not used.
20
VOUT-A
Channel A,
LNB output port
Output of channel A integrated very low drop linear regulator. See
Table 14 for voltage selection and description.
21
VUP-A
Channel A
step-up voltage
Input of channel A linear post-regulator. The voltage on this pin is
monitored by the internal channel A step-up controller to keep a minimum
dropout across the linear pass transistor.
22
DSQIN-A
DSQIN for
DiSEqC envelope
input
or
external 22 kHz
TTL input
It is intended for channel A 22 kHz tone control.
It can be used as DiSEqC envelope input or external 22 kHz TTL input
depending on the EXTM-A I²C bit setting as follows:
If EXTM-A=0, TEN-A=1: it accepts the DiSEqC envelope code from the
main microcontroller. The LNBH26 uses this code to modulate the
internally generated 22 kHz carrier.
If EXTM-A=TEN-A=1: it accepts external 22 kHz logic signals which
activate the 22 kHz tone output (refer to Section 2.2).
Pull up high if the tone output is activated only by the TEN-A I²C bit.
23
DSQOUT-A
DiSEqC output
Open drain output of channel A tone detector to the main microcontroller
for DiSEqC 2.0 data decoding. It is low when tone is detected to the
DETIN-A input pin. Set to ground if not used.
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13/38
Pin configuration
Table 2.
Pin
Pin description (continued)
Symbol
24
DSQIN-B
Epad
Epad
14/38
LNBH26
Name
Pin function
It is intended for channel B 22 kHz tone control.
It can be used as DiSEqC envelope input or external 22 kHz TTL input
DSQIN for
DiSEqC envelope depending on the EXTM-B I²C bit setting as follows:
If EXTM-B=0, TEN-B=1: it accepts the DiSEqC envelope code from the
input
main microcontroller. The LNBH26 uses this code to modulate the
Or
internally generated 22 kHz carrier.
external 22 kHz If EXTM-A=TEN-A=1: it accepts external 22 kHz logic signals which
TTL input
activate the 22 kHz tone output (refer to Section 2.2).
Pull up high if the tone output is activated only by the TEN-B I²C bit.
Exposed pad
To be connected with power grounds and to the ground layer through vias
to dissipate the heat.
Doc ID 022771 Rev 1
LNBH26
Maximum ratings
4
Maximum ratings
Table 3.
Absolute maximum ratings
Symbol
Parameter
Value
Unit
VCC
DC power supply input voltage pins
-0.3 to 20
V
VUP
DC input voltage
-0.3 to 40
V
IOUT
Output current
Internally limited
mA
VOUT
DC output pin voltage
-0.3 to 40
V
VI
Logic input pin voltage (SDA, SCL, DSQIN, ADDR pins)
-0.3 to 7
V
VO
Logic output pin voltage (FLT, DSQOUT)
-0.3 to 7
V
VBPSW
BPSW pin voltage
-0.3 to 40
V
VDETIN
Detector input signal amplitude
-0.6 to 2
V
10
mA
IO
Logic output pin current (FLT, DSQOUT, BPSW)
LX
LX input voltage
-0.3 to 30
V
VBYP
Internal reference pin voltage
-0.3 to 4.6
V
ISEL
Current selection pin voltage
-0.3 to 3.5
V
TSTG
Storage temperature range
-50 to 150
°C
Operating junction temperature range
-25 to 125
°C
TJ
ESD
Table 4.
Symbol
ESD rating with human body model (HBM) for all pins, except power
output pins
2
ESD rating with human body model (HBM) for power output pins
4
kV
Thermal data
Parameter
Value
Unit
RthJC
Thermal resistance junction-case
2
°C/W
RthJA
Thermal resistance junction-ambient with device soldered on 2s2p 4layer PCB provided with thermal vias below exposed pad.
40
°C/W
Note:
Absolute maximum ratings are those values beyond which damage to the device may occur.
These are stress ratings only and functional operation of the device at these conditions is
not implied. Exposure to absolute-maximum-rated conditions for extended periods may
affect device reliability. All voltage values are with respect to network ground terminal.
Doc ID 022771 Rev 1
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Typical application circuits
5
LNBH26
Typical application circuits
Figure 6.
DiSEqC 1.x application circuit
D2-A
LNBOUT-A
21
D1-A
C2-A
VOUT-A
VUP-A
20
LNBH26
C3-A
3
LX-A
9
ISEL
16
Byp
C5-A
D3-A
R1 (RSEL)
L1-A
DSQIN-A
C7
Vin
12V
17
Vcc
DSQIN-B
24
ADDR
6
FLT
2
VOUT-B
11
C4
C1
L1-B
I2C Bus
{
8
SDA
7
SCL
5
LX-B
10
VUP-B
DiSEqC
22KHz
22
Tone enable control
TTL
or
DiSEqC
Envelope
TTL
D1-B
C2-B
P-GND
A-GND
4
15
C3-B
LNBOUT-B
C5-B
D3-B
D2-B
Table 5.
DiSEqC 1.x bill of material (valid for A and B channels except for C1, C4,
C7 and R1)
Component
R1 (RSEL)
C1, C2
Notes
SMD resistor. Refer to Table 13 and ISEL pin description in Table 2
> 25 V electrolytic capacitor, 100 µF is suitable
C3
From 470 nF to 2.2 µF ceramic capacitor. Higher values allow lower DC-DC noise.
C5
From 100 nF to 220 nF ceramic capacitor. Higher values allow lower DC-DC noise.
C4, C7
16/38
AM10477v1
220 nF ceramic capacitors
D1
STPS130A or similar schottky diode
D3
BAT54, BAT43, 1N5818, or any low power schottky diode with IF (AV) > 0.2 A,
VRRM > 25 V, VF < 0 .5 V . To be placed as close as possible to VOUT pin
D2
1N4001-07, S1A-S1M, or any similar general purpose rectifier
L1
10 µH inductor with Isat > Ipeak where Ipeak is the boost converter peak current
Doc ID 022771 Rev 1
LNBH26
Typical application circuits
Figure 7.
DiSEqC 2.x application circuit
D2-A
L2-A
21
VOUT-A
VUP-A
C5-A
LNBOUT-A
D3-A
20
15 Ω
D1-A
C2-A
LNBH26
C3-A
4.7k
BPSW-A
18
4.7k
3
LX-A
DETIN-A
19
DSQOUT-A
23
DSQIN-A
22
TR1-A
10k
R1 (RSEL)
L1-A
9
ISEL
16
Byp
C7
Vin
12V
17
Vcc
DSQIN-B
24
ADDR
6
FLT
2
C4
C1
L1-B
I2C Bus
{
8
SDA
7
SCL
5
LX-B
DSQOUT-B
1
DETIN-B
12
BPSW-B
13
C6-A
DiSEqC
22KHz
Tone enable control
DiSEqC
Envelope
Open drains
to µController
TTL
C6-B
10k
TR1-B
4.7k
D1-B
TTL
or
4.7k
10
C2-B
15 Ω
VUP-B
VOUT-B
P-GND
A-GND
4
15
C3-B
11
LNBOUT-B
C5-B
D3-B
L2-B
D2-B
Table 6.
DiSEqC 2.x bill of material (valid for A and B channels except for C1, C4,
C7 and R1)
Component
R1 (RSEL)
C1, C2
AM10478v1
Notes
SMD resistors. Refer to Table 13 and ISEL pin description in Table 2
> 25 V electrolytic capacitor, 100 µF is suitable
C3
From 470 nF to 2.2 µF ceramic capacitor. Higher values allow lower DC-DC noise.
C5
From 100 nF to 220 nF ceramic capacitor. Higher values allow lower DC-DC noise.
C4, C7
220 nF ceramic capacitors
C6
10 nF ceramic capacitors
D1
STPS130A or similar schottky diode
D3
BAT54, BAT43, 1N5818, or any low power schottky diode with IF (AV) > 0.2 A,
VRRM > 25 V, VF < 0 .5 V . To be placed as close as possible to VOUT pin
D2
1N4001-07, S1A-S1M, or any similar general purpose rectifier
L1
10 µH inductor with Isat > Ipeak where Ipeak is the boost converter peak current
L2
220 µH inductor
TR1
2STR2160 or 2STF2340 or any small power PNP with IC > 250 mA, VCE > 30 V, can
be used.
Also any small power PMOS with ID > 250 mA, RDSON < 0.5Ω, VDS > 20 V, can be
used.
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I²C bus interface
6
LNBH26
I²C bus interface
Data transmission from the main microprocessor to the LNBH26 and vice versa takes place
through the 2-wire I²C bus interface, consisting of the 2-line SDA and SCL (pull-up resistors
to positive supply voltage must be externally connected).
6.1
Data validity
As shown in Figure 8, the data on the SDA line must be stable during the high semi-period
of the clock. The HIGH and LOW state of the data line can only change when the clock
signal on the SCL line is LOW.
6.2
Start and stop condition
As shown in Figure 9, a start condition is a HIGH to LOW transition of the SDA line while
SCL is HIGH. The stop condition is a LOW to HIGH transition of the SDA line while SCL is
HIGH. A STOP condition must be sent before each START condition.
6.3
Byte format
Every byte transferred to the SDA line must contain 8 bits. Each byte must be followed by an
acknowledge bit. The MSB is transferred first.
6.4
Acknowledge
The master (microprocessor) puts a resistive HIGH level on the SDA line during the
acknowledge clock pulse (see Figure 10). The peripheral (LNBH26) which acknowledges
must pull down (LOW) the SDA line during the acknowledge clock pulse, so that the SDA
line is stable LOW during this clock pulse. The peripheral which has been addressed must
generate acknowledge after the reception of each byte, otherwise the SDA line remains at
the HIGH level during the ninth clock pulse time. In this case the master transmitter can
generate the STOP information in order to abort the transfer. The LNBH26 does not
generate acknowledge if the VCC supply is below the undervoltage lockout threshold (4.7 V
typ.).
6.5
Transmission without acknowledge
If detection of the acknowledge of the LNBH26 is not required, the microprocessor can use
a simpler transmission: it simply waits one clock without checking the slave acknowledging,
and sends the new data. This approach is of course less protected from misworking and
decreases noise immunity.
18/38
Doc ID 022771 Rev 1
LNBH26
I²C bus interface
Figure 8.
Data validity on the I²C bus
Figure 9.
Timing diagram of I²C bus
Figure 10. Acknowledge on the I²C bus
Doc ID 022771 Rev 1
19/38
I²C interface protocol
LNBH26
7
I²C interface protocol
7.1
Write mode transmission
The LNBH26 interface protocol is made up of:
●
a start condition (S)
●
a chip address byte with the LSB bit R/W = 0
●
a register address (internal address of the first register to be accessed)
●
a sequence of data (byte to write in the addressed internal register + acknowledge)
●
the following bytes, if any, to be written in successive internal registers
●
a stop condition (P). The transfer lasts until a stop bit is encountered
●
the LNBH25, as slave, acknowledges every byte transfer.
Figure 11. Example of writing procedure starting with first data address 0x2 (a)
CHIP ADDRESS
LSB
MSB
0 X
0 0 0 0 0 X X X
DATA 3
Add=0x4
DATA 2
Add=0x3
DATA 1
Add=0x2
MSB
ACK
0 0 1 0
LSB
MSB
ACK
0
R/W = 0
S
REGISTER ADDRESS
MSB
LSB
MSB
LSB
DATA 4
Add=0x5
LSB
MSB
LSB
ACK
N/A
EN_IMON-A
N/A
OLR
N/A
EN_IMON-B
ACK
THERM
COMP
ACK
ISET-A
ISW-A
PCL-A
TIMER-A
ISET-B
ISW-B
PCL-B
TIMER-B
N/A
TEN-A
LPM -A
EXTM-A
N/A
TEN-B
LPM-B
EXTM-B
ACK
VSEL1-A
VSEL2-A
VSEL3-A
VSEL4-A
VSEL1-B
VSEL2-B
VSEL3-B
VSEL4-B
P
AM10479v1
ACK = Acknowledge
S = Start
P = Stop
R/W = 1/0, Read/Write bit
X = 0/1, set the values to select the CHIP address (see Table 16 for pin selection) and to
select the REGISTER address (see Table 7 to Table 12).
a. The writing procedure can start from any register address by simply setting the X values in the register address
byte (after the chip address). It can be also stopped by the master by sending a stop condition after any
acknowledge bit.
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Doc ID 022771 Rev 1
LNBH26
I²C interface protocol
7.2
Read mode transmission
In read mode the bytes sequence must be as follows:
●
a start condition (S)
●
a chip address byte with the LSB bit R/W=0
●
the register address byte of the internal first register to be accessed
●
a stop condition (P)
●
a new master transmission with the chip address byte and the LSB bit R/W=1
●
after the acknowledge the LNBH26 starts to send the addressed register content. As
long as the master keeps the acknowledge LOW, the LNBH26 transmits the next
address register byte content.
●
the transmission is terminated when the master sets the acknowledge HIGH with a
following stop bit.
Figure 12. Example of reading procedure starting with first status address 0X0 (b)
REGISTER ADDRESS
CHIP ADDRESS
LSB
MSB
P
ACK
TDET-A
TDET-B
TMON-A
TMON-B
IMON-A
IMON-B
MSB
0 X
DATA 3
Add=0x4
DATA 2
Add=0x3
LSB
0 0 1 0
LSB
N/A
N/A
ACK
OLF-A
OLF-B
VMON-A
VMON-B
PDO-A
PDO-B
OTF
PNG
MSB
MSB
LSB
DATA 1
Add=0x2
0
STATUS 2
Add=0x1
STATUS 1
Add=0x0
MSB
S
ACK
0 0 0 0 0 X X X
R/W = 1
0 X
LSB
MSB
ACK
0 0 1 0
LSB
MSB
ACK
0
R/W = 0
S
CHIP ADDRESS
MSB
LSB
DATA 4
Add=0x5
LSB
MSB
LSB
ACK
N/A
EN_IMON-A
N/A
OLR
N/A
EN_IMON-B
ACK
THERM
COMP
ACK
ISET-A
ISW-A
PCL-A
TIMER-A
ISET-B
ISW-B
PCL-B
TIMER-B
N/A
TEN-A
LPM -A
EXTM-A
N/A
TEN-B
LPM-B
EXTM-B
ACK
VSEL1-A
VSEL2-A
VSEL3-A
VSEL4-A
VSEL1-B
VSEL2-B
VSEL3-B
VSEL4-B
P
AM10480v1
ACK = Acknowledge
S = Start
P = Stop
R/W = 1/0, Read/Write bit
X = 0/1, set the values to select the CHIP address (see Table 16 for pin selection) and to
select the REGISTER address (see Table 7 to Table 12).
b. The reading procedure can start from any register address (Status 1, 2 or Data1..4) by simply setting the X
values in the register address byte (after the first chip address in the above figure). It can be also stopped by
the master by sending a stop condition after any acknowledge bit.
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I²C interface protocol
7.3
LNBH26
Data registers
The DATA 1..4 registers can be addressed both in write and read mode. In read mode they
return the last writing byte status received in the previous write transmission.
The following tables provide the register address values of Data 1..4 and a function
description of each bit.
Table 7.
DATA 1 (Read/Write register. Register address = 0X2)
Bit
Name
Bit 0
(LSB)
VSEL1-A
Bit 1
VSEL2-A
Bit 2
VSEL3-A
0/1
Bit 3
VSEL4-A
0/1
Bit 4
VSEL1-B
0/1
Bit 5
VSEL2-B
Bit 6
VSEL3-B
Bit 7
(MSB)
VSEL4-B
CH
Value
Description
0/1
A
Channel A
Output voltage selection bits.
(Refer to Table 14)
0/1
0/1
B
Channel B
Output voltage selection bits.
(Refer to Table 14)
0/1
0/1
N/A = Reserved bit.
All bits reset to “0” at power-on.
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Doc ID 022771 Rev 1
LNBH26
Table 8.
I²C interface protocol
DATA 2 (Read/Write register. Register address = 0X3)
Bit
Name
Bit 0
(LSB)
TEN-A
Bit 1
CH
N/A
Bit 4
TEN-B
Bit 7
(MSB)
0
22 kHz tone output disabled
1
Low power mode activated (used only with 22 kHz tone output disabled)
0
Low power mode deactivated (keep always LPM=0 during 22 kHz tone
transmission)
1
DSQIN input pin is set to receive external 22 kHz TTL signal source
0
DSQIN input pin is set to receive external DiSEqC envelope TTL signal
0
Reserved. Keep to “0”
1
22 kHz tone enabled. Tone output controlled by the DSQIN pin
0
22 kHz tone output disabled
1
Low power mode activated (used only with 22 kHz tone output disabled)
0
Low power mode deactivated (keep always LPM=0 during 22 kHz tone
transmission)
1
DSQIN input pin is set to receive external 22 kHz TTL signal source
0
DSQIN input pin is set to receive external DiSEqC envelope TTL signal
0
Reserved. Keep to “0”
LPM-B
B
Bit 6
22 kHz tone enabled. Tone output controlled by the DSQIN pin
EXTM-A
Bit 3
Bit 5
Description
1
LPM-A
A
Bit 2
Value
EXTM-B
N/A
N/A = Reserved bit.
All bits reset to 0 at power-on.
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I²C interface protocol
Table 9.
Bit
Bit 0
(LSB)
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
(MSB)
LNBH26
DATA 3 (Read/Write register. Register address = 0X4)
Name
CH
Value
Description
1
Current limit of LNB output (Vout pin) set to lower current range:
Refer to Section 2.5 in application information section.
0
Current limit of LNB output (Vout pin) set to default range:
Refer to Section 2.5 in application information section.
1
DC-DC, inductor switching current limit set to 2.5 A typ.
0
DC-DC, inductor switching current limit set to 4 A typ.
1
Pulsed (Dynamic) LNB output current limiting is deactivated
0
Pulsed (Dynamic) LNB output current limiting is activated
1
Pulsed (Dynamic) LNB output current TON time set to 180 ms typ.
0
Pulsed (Dynamic) LNB output current TON time set to 90 ms typ.
1
Current limit of LNB output (VOUT pin) set to lower current range:
Refer to Section 2.5 in the application information section.
0
Current limit of LNB output (VOUT pin) set to default range:
Refer to Section 2.5 in the application information section.
1
DC-DC, inductor switching current limit set to 2.5 A typ.
0
DC-DC, inductor switching current limit set to 4 A typ.
1
Pulsed (Dynamic) LNB output current limiting is deactivated
0
Pulsed (Dynamic) LNB output current limiting is activated
1
Pulsed (Dynamic) LNB output current TON time set to 180 ms typ.
0
Pulsed (Dynamic) LNB output current TON time set to 90 ms typ.
ISET-A
ISW-A
A
PCL-A
TIMER-A
ISET-B
ISW-B
B
PCL-B
TIMER-B
N/A = Reserved bit.
All bits reset to 0 at power-on.
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Doc ID 022771 Rev 1
LNBH26
Table 10.
Bit
I²C interface protocol
DATA 4 (Read/Write register. Register address = 0X5)
Name
Bit 0 EN_IMON(LSB)
A
CH
Value
Description
1
IMON diagnostic function is enabled. (VOUT is set to 21 V typ.)
0
IMON diagnostic function is disabled. Keep always at “0” if IMON is not used.
A
Bit 1
N/A
0
Reserved. Keep to “0”
Bit 2
N/A
0
Reserved. Keep to “0”
1
In the case of overload protection activation (OLF=1), all VSEL bits are reset
to “0” and LNB relevant output (VOUT pin) is disabled. The VSEL bits must be
set again by the master after the overcurrent condition is removed (OLF=0).
0
In the case of overload protection activation (OLF=1) the LNB output (VOUT
pin) is automatically enabled as soon as the overload condition is removed
(OLF=0) with the previous VSEL bit setting.
1
IMON diagnostic function is enabled
0
IMON diagnostic function is disabled. Keep always at “0” if IMON is not used.
0
Reserved. Keep to “0”
1
If thermal protection is activated (OTF=1), all VSEL bits are reset to “0” and
LNB output (VOUT pin) is disabled (both section A & B). The VSEL bits must
be set again by the master after the overtemperature condition is removed
(OTF=0).
0
In the case of thermal protection activation (OTF=1) the LNB output (VOUT
pin) is automatically enabled as soon as the overtemperature condition is
removed (OTF=0) with the previous VSEL bit setting.
1
DC-DC converter compensation set to use HIGH E.S.R. capacitors (VUP pin)
0
DC-DC converter compensation set to use LOW E.S.R. capacitors (VUP pin)
Bit 3
Bit 4
Bit 5
Bit 6
OLR
EN_IMONB
A/B
B
N/A
THERM
A/B
Bit 7
(MSB)
COMP
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I²C interface protocol
7.4
LNBH26
Status registers
The STATUS 1, 2 registers can be addressed only in read mode and provide the diagnostic
functions described in the following tables.
Table 11.
STATUS 1 (Read register. Register address = 0X0)
Bit
Name
CH
Bit 0
(LSB)
OLF-A
A
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
(MSB)
OLF-B
VMON-A
VMON-B
PDO-A
PDO-B
OTF
PNG
Value
Description
1
VOUT pin overload protection has been triggered (IOUT > IMAX). Refer to Table 9
for the overload operation settings (ISET, PCL, TIMER bits).
0
No overload protection has been triggered to VOUT pin (IOUT < IMAX).
1
VOUT pin overload protection has been triggered (IOUT > IMAX). Refer to Table 9
for the overload operation settings (ISET, PCL, TIMER bits).
0
No overload protection has been triggered to VOUT pin (IOUT < IMAX).
1
Output voltage (VOUT pin) lower than VMON specification thresholds. Refer to
Table 17.
0
Output voltage (VOUT pin) is within the VMON specifications.
1
Output voltage (VOUT pin) lower than VMON specification thresholds. Refer to
Table 17.
0
Output voltage (VOUT pin) is within the VMON specifications.
1
Overcurrent detected on output pull-down stage for a time longer than the
deglitch period. This may happen due to an external voltage source present on
the LNB output (VOUT pin).
0
No overcurrent detected on output pull-down stage.
1
Overcurrent detected on output pull-down stage for a time longer than the
deglitch period. This may happen due to an external voltage source present on
the LNB output (VOUT pin).
0
No overcurrent detected on output pull-down stage.
1
Junction overtemperature is detected, TJ > 150 °C (typ.). See also the THERM
bit setting in Table 10.
0
Junction overtemperature not detected, TJ <135 °C (typ.). TJ is below thermal
protection threshold.
1
Input voltage (VCC pin) lower than LPD minimum thresholds. Refer to Table 13.
0
Input voltage (VCC pin) higher than LPD thresholds. Refer to Table 13.
B
A
B
A
B
A/B
A/B
N/A = Reserved bit.
All bits reset to 0 at power-on.
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Doc ID 022771 Rev 1
LNBH26
I²C interface protocol
Table 12.
STATUS 2 (Read register. Register address = 0X1)
Bit
Name
CH
Bit 0
(LSB)
TDET-A
A
Bit 1
TDET-B
Bit 2
Bit 3
Bit 4
Bit 5
TMON-A
TMON-B
IMON-A
IMON-B
Value
Description
1
22 kHz tone presence is detected on the DETIN pin
0
No 22 kHz tone is detected on the DETIN pin
1
22 kHz tone presence is detected on the DETIN pin
0
No 22 kHz tone is detected on the DETIN pin
1
22 kHz tone present on the DETIN pin is out of TMON specification thresholds.
That is: the tone frequency or the ATONE (tone amplitude) are out of the
thresholds guaranteed in Table 19.
0
22 kHz tone present on the DETIN pin is within TMON specification
thresholds. Refer to Table 19.
1
22 kHz tone present on the DETIN pin is out of TMON specification thresholds.
That is: the tone frequency or the ATONE (tone amplitude) are out of the
thresholds guaranteed in Table 19.
0
22 kHz tone present on DETIN pin is within TMON specification thresholds.
Refer to Table 19.
1
Output current (from VOUT pin) is lower than IMON specification thresholds.
Refer to Table 18.
0
Output current (from VOUT pin) is higher than IMON specifications.
Refer to Table 18.
1
Output current (from VOUT pin) is lower than IMON specification thresholds.
Refer to Table 18.
0
Output current (from VOUT pin) is higher than IMON specifications.
Refer to Table 18.
B
A
B
A
B
Bit 6
N/A
-
Reserved
Bit 7
(MSB)
N/A
-
Reserved
N/A = Reserved bit.
All bits reset to 0 at power-on.
Doc ID 022771 Rev 1
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Electrical characteristics
8
LNBH26
Electrical characteristics
Refer to Section 5, TJ from 0 to 85 °C, all DATA 1..4 register bits set to 0 except VSEL1 = 1,
RSEL = 11 kΩ, DSQIN = LOW, VIN = 12 V, IOUT = 50 mA, unless otherwise stated. Typical
values are referred to TJ = 25 °C. VOUT = VOUT pin voltage. See software description section
for I²C access to the system register (Section 6 and Section 7).
Table 13.
Symbol
VIN
IIN
Electrical characteristics of section A/B
Parameter
Test conditions
Supply voltage (1)
Supply current
8
12
16
V
19
Both sections A and B set in standby:
VSEL1=VSEL2=VSEL3=VSEL4=0
2
VOUT
Line regulation
VIN = 8 to 16 V
VOUT
Load regulation
IOUT from 50 to 750 mA
Output current limiting thresholds
Unit
22 kHz tone enabled (TEN-A/B = 1,
DSQIN-A/B = High), IOUT = 0 mA
Valid at any VOUT selected level
IMAX
Max.
12
Output voltage total accuracy
Output current limiting thresholds
Typ.
Both sections A and B enabled,
IOUT = 0 mA
VOUT
IMAX
Min.
-3.5
mA
+3.5
%
40
mV
100
RSEL = 11 kΩ, ISET = 0
750
1100
RSEL = 15 kΩ, ISET = 0
500
750
RSEL = 20 kΩ, ISET = 0
350
550
mA
RSEL = 11 kΩ, ISET = 1
400
RSEL = 15 kΩ, ISET = 1
280
RSEL = 20 kΩ, ISET = 1
200
500
mA
mA
ISC
Output short-circuit current
RSEL = 11 kΩ, ISET = 0
SS
Soft-start time
VOUT from 0 to 13 V
4
ms
SS
Soft-start time
VOUT from 0 to 18 V
6
ms
T13-18
Soft transition rise time
VOUT from 13 V to 18 V
1.5
ms
T18-13
Soft transition fall time
VOUT from 18 V to 13 V
1.5
ms
Dynamic overload protection OFF
PCL = 0, output shorted
time
900
ms
TOFF
TON
ATONE
28/38
PCL = TIMER = 0, output shorted
TOFF/
10
PCL = 0, TIMER = 1, output shorted
TOFF/
5
Dynamic overload protection ON
time
Tone amplitude
DSQIN=High, EXTM=0, TEN=1
IOUT from 0 to 750 mA
CBUS from 0 to 750 nF
Doc ID 022771 Rev 1
0.55 0.675
0.8
VPP
LNBH26
Table 13.
Symbol
Electrical characteristics
Electrical characteristics of section A/B (continued)
Parameter
FTONE
Tone frequency
DTONE
Tone duty cycle
tr, tf
Tone rise or fall time
DSQIN=High, EXTM=0, TEN=1
(2)
EffDC/DC DC-DC converter efficiency
FSW
UVLO
Test conditions
Min.
Typ.
Max.
Unit
20
22
24
kHz
43
50
57
%
5
8
15
µs
IOUT = 500 mA
93
%
440
kHz
UVLO threshold rising
4.8
V
UVLO threshold falling
4.7
VLP threshold rising
7.2
VLP threshold falling
6.7
DC-DC converter switching
frequency
Undervoltage lockout thresholds
V
VLP
Low power diagnostic (LPD)
thresholds
VIL
DSQIN, pin logic low
VIH
DSQIN, pin logic high
IIH
DSQIN, pin input current
VIH = 5 V
FDETIN
Tone detector frequency capture
range
0.4 VPP sine wave (3)
19
VDETIN
Tone detector input amplitude
Sine wave signal, 22 kHz
0.3
ZDETIN
Tone detector input impedance
VOL
DSQOUT, FLT pins logic LOW
DETIN tone present, IOL = 2 mA
0.3
BPSW pin low voltage
IOL_BPSW = 5 mA
DSQIN = high, EXTM = 0, TEN = 1
0.7
IOZ
DSQOUT, FLT pins leakage
current
DETIN tone absent, VOH = 6 V
IOBK
Output backward current
All VSELx = 0, VOBK = 30 V
-3
ISINK
Output low-side sink current
VOUT forced at VOUT_nom+0.1 V
70
mA
Low-side sink current time-out
VOUT forced at VOUT_nom+0.1 V.
PDO I²C bit is set to 1 after this time is
elapsed.
10
ms
Max. reverse current
VOUT forced at VOUT_nom+0.1 V,
after PDO bit is set to 1 (ISINK_TIMEOUT elapsed).
2
mA
VOL_BPS
W
ISINK_TIM
E-OUT
IREV
0.8
V
2
V
15
22
µA
25
kHz
1.5
VPP
150
kΩ
0.5
V
V
10
µA
-6
mA
TSHDN
Thermal shutdown threshold
150
°C
ΔTSHDN
Thermal shutdown hysteresis
15
°C
1. In applications where (VCC - VOUT) > 1.3 V, the increased power dissipation inside the integrated LDO must be taken into
account in the application thermal management design.
2. Guaranteed by design.
3. Frequency range in which the DETIN function is guaranteed. The Vpp level is intended on the LNB bus (before the C6
capacitor. See typical application circuit for DiSEqC 2.x) IOUT from 0 to 750 mA, CBUS from 0 to 750 nF.
Doc ID 022771 Rev 1
29/38
Electrical characteristics
8.1
LNBH26
Output voltage selection
Each LNBH26 channel is provided with 15 output voltage levels (7 levels for 13 V range
when VSEL4-A/B=0 and 8 levels for 18 V range when VSEL4-A/B=1) which can be selected
through the register Data1. Table 14 shows the output voltage values corresponding to
VSELx bit combinations both for channel A and B. If all VSELx are set to “0” the device is set
in standby mode and the VOUT-A/B is disabled.
Table 14.
Output voltage selection table (Data1 register, write mode) (1)
VOUT
min.
VOUT -A/B
pin
voltage
VSEL4A/B
VSEL3A/B
VSEL2A/B
VSEL1A/B
0
0
0
0
0
0
0
1
12.545
13.000
13.455
0
0
1
0
12.867
13.333
13.800
0
0
1
1
13.188
13.667
14.145
0
1
0
0
13.51
14.000
14.490
0
1
0
1
13.832
14.333
14.835
0
1
1
0
14.153
14.667
15.180
0
1
1
1
14.475
15.000
15.525
1
0
0
0
17.515
18.150
18.785
1
0
0
1
17.836
18.483
19.130
1
0
1
0
18.158
18.817
19.475
1
0
1
1
18.48
19.150
19.820
1
1
0
0
18.801
19.483
20.165
1
1
0
1
19.123
19.817
20.510
1
1
1
0
19.445
20.150
20.855
1
1
1
1
19.766
20.483
21.200
VOUT
max.
Function
VOUT -A/B disabled. LNBH26 set in
standby mode
0
1. TJ from 0 to 85 °C, VI = 12 V.
TJ from 0 to 85 °C, VI = 12 V.
Table 15.
Symbol
I²C electrical characteristics
Parameter
Test conditions
VIL
Low level input voltage
SDA, SCL
VIH
High level input voltage
SDA, SCL
IIN
Input current
VOL
FMAX
Low level output voltage
SDA, SCL, VIN = 0.4 to 4.5 V
(1)
Maximum clock frequency
SCL
-10
400
Doc ID 022771 Rev 1
Typ.
Max.
Unit
0.8
V
2
SDA (open drain), IOL = 6 mA
1. Guaranteed by design.
30/38
Min.
V
10
µA
0.6
V
kHz
LNBH26
Electrical characteristics
TJ from 0 to 85 °C, VI = 12 V.
Table 16.
Address pin characteristics
Symbol
Parameter
Test condition
Min.
VADDR-1
“0001000(R/W)” address pin
voltage range
R/W bit determines the transmission
mode: read (R/W=1) write (R/W=0)
VADDR-2
“0001001(R/W)” address pin
voltage range
R/W bit determines the transmission
mode: read (R/W=1) write (R/W=0)
Typ.
Max.
Unit
0
0.8
V
2
5
V
Refer to Section 5, TJ from 0 to 85 °C, All DATA 1..4 register bits set to “0”, RSEL = 11 kΩ,
DSQIN = LOW, VIN = 12 V, IOUT = 50 mA, unless otherwise stated. Typical values are
referred to TJ = 25 °C. VOUT = VOUT pin voltage. See software description section for I²C
access to the system register.
Table 17.
Symbol
Output voltage diagnostic (VMON-A/B bits, STATUS 1 register) characteristics
Parameter
Test condition
Min.
Typ.
Max.
Unit
VTH-L
Diagnostic low threshold at
VOUT = 13.0 V
VSEL1 = 1,
VSEL2 = VSEL3 = VSEL4 = 0
80
90
95
%
VTH-L
Diagnostic low threshold at
VOUT = 18.15 V
VSEL4=1,
VSEL1 = VSEL2 = VSEL3 = 0
80
90
95
%
Note:
If the output voltage is lower than the min. value the VMON I²C bit is set to 1.
If VMON=0 then VOUT > 80% of VOUT (typ.).
If VMON=1 then VOUT < 95% of VOUT (typ.).
Refer to Section 5, TJ from 0 to 85 °C, RSEL = 11 kΩ, DSQIN = LOW, VIN = 12 V, unless
otherwise stated. Typical values are referred to TJ = 25 °C. VOUT = VOUT pin voltage. See
software description section for I²C access to the system register.
Table 18.
Symbol
ITH
Note:
Output current diagnostic (IMON-A/B bit, STATUS 2 register) characteristics
Parameter
Minimum current diagnostic
threshold
Test condition
Min.
Typ.
Max.
Unit
EN_IMON = 1 (VOUT is set to 21 V typ.)
5
12
20
mA
If the output current is lower than the min. threshold limit, the IMON I²C bit is set to 1. If the
output current is higher than the max. threshold limit, the IMON I²C bit is set to 0.
Doc ID 022771 Rev 1
31/38
Electrical characteristics
LNBH26
Refer to Section 5, TJ from 0 to 85 °C, All DATA 1..4 register bits set to “0” except
VSEL1 = 1, TEN=1, RSEL = 11 kΩ, DSQIN = HIGH, VIN = 12 V, IOUT = 50 mA, unless
otherwise stated. Typical values are referred to TJ = 25 °C. VOUT = VOUT pin voltage. See
software description section for I²C access to the system register.
Table 19.
Symbol
22 kHz tone diagnostic (TMON-A/B bit, STATUS 2 register) characteristics
Parameter
Test condition
Min.
Typ.
Max.
Unit
ATH-L
Amplitude diagnostic low threshold DETIN pin AC coupled
200
300
400
mV
ATH-H
Amplitude diagnostic high
threshold
DETIN pin AC coupled
900
1100
1200
mV
FTH-L
Frequency diagnostic low
thresholds
DETIN pin AC coupled
13
16.5
20
kHz
FTH-H
Frequency diagnostic high
thresholds
DETIN pin AC coupled
24
29.5
38
kHz
Note:
32/38
If the 22 kHz tone parameters are lower or higher than the above limits, the TMON I²C bit is
set to “1”.
Doc ID 022771 Rev 1
LNBH26
9
Package mechanical data
Package mechanical data
In order to meet environmental requirements, ST offers these devices in different grades of
ECOPACK® packages, depending on their level of environmental compliance. ECOPACK
specifications, grade definitions and product status are available at: www.st.com. ECOPACK
is an ST trademark.
Table 20.
QFN24L (4 x 4 mm) mechanical data
(mm.)
Dim.
Min.
Typ.
Max.
A
0.80
0.90
1.00
A1
0.00
0.02
0.05
b
0.18
0.25
0.30
D
3.90
4.00
4.10
D2
2.55
2.70
2.80
E
3.90
4.00
4.10
E2
2.55
2.70
2.80
e
0.45
0.50
0.55
L
0.25
0.35
0.45
Doc ID 022771 Rev 1
33/38
Package mechanical data
LNBH26
Figure 13. QFN24L (4 x 4 mm) package dimensions
7596209_D
34/38
Doc ID 022771 Rev 1
LNBH26
Package mechanical data
Tape & reel QFNxx/DFNxx (4x4) mechanical data
mm.
inch.
Dim.
Min.
Typ.
A
Max.
Min.
Typ.
330
C
12.8
D
20.2
N
99
13.2
Max.
12.992
0.504
0.519
0.795
101
T
3.898
3.976
14.4
0.567
Ao
4.35
0.171
Bo
4.35
0.171
Ko
1.1
0.043
Po
4
0.157
P
8
0.315
Doc ID 022771 Rev 1
35/38
Package mechanical data
LNBH26
Figure 14. QFN24L (4 x 4) footprint recommended data (mm.)
36/38
Doc ID 022771 Rev 1
LNBH26
Revision history
10
Revision history
Table 21.
Document revision history
Date
Revision
03-Feb-2012
1
Changes
Initial release.
Doc ID 022771 Rev 1
37/38
LNBH26
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