LM48100QMH/NOPB National Semiconductor, LM48100QMH/NOPB Datasheet - Page 14

• Manufacturer Part Number: LM48100QMH/NOPB
• Description: IC AMP AUDIO PWR 1.6W 14ETSSOP
• Manufacturer: National Semiconductor
• Series: Boomer®, PowerWise®r
• Type: Class ABr

Specifications of LM48100QMH/NOPB

• Output Type: 1-Channel (Mono)
• Max Output Power X Channels @ Load: 1.6W x 1 @ 8 Ohm
• Voltage - Supply: 3 V ~ 5.5 V
• Features: Depop, I²C, Input Multiplexer, Short-Circuit and Thermal Protection, Shutdown, Volume Control
• Mounting Type: Surface Mount
• Package / Case: 14-TSSOP Exposed Pad, 14-eTSSOP 14-HTSSOP
• Amplifier Class: AB
• No. Of Channels: 1
• Output Power: 1.3W
• Supply Voltage Range: 3V To 5.5V
• Load Impedance: 8ohm
• Operating Temperature Range: -40°C To +105°C
• Amplifier Case Style: TSSOP
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM48100QMH

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DIAGNOSTIC CONTROL
The LM48100Q output fault diagnostics are controlled
through the I
the device, the LM48100Q initializes, performing the full di-
agnostic sequence; output short to V
shorted together, and no load condition, is performed. The
device remains in shutdown while the initial diagnostic check
is performed. Any I
this time are stored and implemented once the diagnostic
check is complete. The initial diagnostic sequence can be
terminated by setting DG_RESET = 1.
The Diagnostic Control register, register 1, controls the
LM48100Q diagnostic process. Bit B4, DG_EN, enables the
output fault detection. Set DG_EN = 1 to enable the output
diagnostic test sequence. The LM48100Q treats the DG_EN
bit as rising-edge-sensitive; once DG_EN = 1 is clocked into
the device, the diagnostic test is performed. If the LM48100Q
is in one-shot mode, once the test sequence is performed, the
DG_EN bit is ignored and the test sequence will not be run
again. Cycle DG_EN from high-to-low-to-high to re-enable
the one-shot diagnostic test sequence.
In continuous diagnostic mode, the test sequence is repeated
until either a fault condition occurs, DG_RESET is cycled, or
the device is taken out of continuous diagnostic mode. Set
DG_CONT = 1 before setting DG_EN = 1 to initiate a contin-
uous diagnostic. Set DG-CONT = 0 to disable continuous
diagnostic mode. When the device is active and DG_EN = 0,
the LM48100Q does not perform the output short, or no load
diagnostics, however, the thermal overload and output over
current protection circuitry remains active, and disables the
device should a thermal or over-current fault occur. The initial
diagnostic operation when power is applied to the device oc-
curs regardless of the state of DG_EN. The LM48100Q output
fault detection can be set to either continuous mode where
the output diagnostic occurs every 60ms, or a one-shot mode.
Set bit B3 (DG_CONT) to 1 for continuous mode, set B3 = 0
for one-shot mode.
Bit B2, DG_RESET, restores the LM48100Q to normal oper-
ation after an output fault is detected. Toggle DG_RESET to
re-enable the device outputs and set FAULT high.
2
C interface. When power is initially applied to
2
C commands written to the device during
DD
and GND, outputs
14
FAULT DETECTION CONTROL REGISTER
The LM48100Q output fault tests are individually controlled
through the Fault Detection Control register, register 2. Set-
ting any of the bits in the Fault Detection Control register to 1
causes the FAULT circuitry to ignore the associated test. For
example, if B2 (RAIL_SHT) = 1 and the output is shorted to
V
circuitry ignores the selected test, the LM48100Q protection
circuitry remains active, and disables the device. This feature
is useful for diagnosing which fault caused a FAULTcondition.
If DG_EN = 1, and a diagnostic sequence is initiated, all the
tests are performed regardless of their state in the Fault De-
tection Control register. If DG_EN = 0, the RAIL_SHT,
OUTPUT_OPEN and OUTPUT_SHT tests are not per-
formed, however, the thermal overload and output over-cur-
rent detection circuitry remains active.
DD
BIT
BIT
B0
B1
B2
B3
B4
B0
B1
B2
B3
B4
, the FAULT output remains high. Although the FAULT
OUTPUT
OUTPUT
TABLE 5. Fault Detection Control Register
RESERVED
_OPEN
NAME
_SHT
_SHT
RAIL
_RESET
OVF
TABLE 4. Diagnostic Control Register
TSD
DG_EN
_CONT
NAME
ILIMIT
DG
DG
VALUE
0
1
0
1
0
1
0
1
0
1
VALUE
0
0
1
0
1
0
1
0
1
Normal operation
Ignore output short circuit fault
(outputs shorted together)
Normal operation
Ignore output short circuit fault
Normal operation
Ignore output short to V
GND fault
Normal operation
Ignore output over-current fault
Normal operation
Ignore thermal overload fault
Unused
Fixed output current limit
Supply dependent output
current limit
Normal operation. FAULT
remains low and device is
disabled once a fault
occurs.
Reset FAULT output.
Device returns to pre-fault
operation.
One shot diagnostic
Continuous diagnostic
Disable diagnostic
Enable diagnostic
DESCRIPTION
DESCRIPTION
DD
or