STA530 ,4X30W STEREO BASH POWER AMPLIFIERBLOCK DIAGRAMGND +V -V PWR_INP1 STBY/MUTE PWR_INP3S SCD+1&2 CD+3&4TURN-ON/OFFSEQUENCEOUT1+ OUT3++10 ..
STA533WF ,18 V, 3 A quad power half-bridgeAbsolute maximum ratingsSymbol Parameter Value UnitV DC supply voltage (Pins 4, 7, 12, 15) 23 VCCV ..
STA533WF13TR ,18 V, 3 A quad power half-bridgeElectrical characteristics Symbol Parameter Test conditions Min Typ Max UnitP Output power in BTL m ..
STA533WF13TR ,18 V, 3 A quad power half-bridgeFeatures■ Multipower BCD technology■ Low input/output pulse width distortion■ 200-mΩ R complementar ..
STA540 ,4 x 13 W dual/quad power amplifierFeatures■ High output power capability– 2x 38 W into 4 Ω at 18 V, 1 kHz, 10% THD– 2x 34 W into 8 Ω ..
STA550 ,70+70W STEREO BASH POWER AMPLIFIERBLOCK DIAGRAM+VS GND -VS OUT_ PRE1 TRK_1 PWR_INP1ABSOLUTE CD+1+VALUE+2OUT1+- BLOCKD G -1IN_PRE1 OUT ..
STTH16R04CT ,Ultrafast recovery diodesFeatures and benefitsSTTH16R04CT STTH16R04CFP■ Very low switching losses■ High frequency and/or hig ..
STTH1L06 ,TURBO 2 ULTRAFAST HIGH VOLTAGE RECTIFIERELECTRICAL CHARACTERISTICSSymbol Parameter Tests conditions Min. Typ. Max. UnitI Reverse leakage V ..
STTH1L06A ,TURBO 2 ULTRAFAST HIGH VOLTAGE RECTIFIERapplications.ABSOLUTE RATINGS (limiting values)Symbol Parameter Value UnitV Repetitive peak reverse ..
STTH1L06U ,TURBO 2 ULTRAFAST HIGH VOLTAGE RECTIFIERFEATURES AND BENEFITSn Ultrafast switchingn Low reverse recovery currentn Reduces switching & condu ..
STTH1R02 ,Ultrafast recovery diodeFeatures and benefitsDO-15DO-41KK■ Very low conduction lossesSTTH1R02QSTTH1R02■ Negligible switchin ..
STTH1R02A ,Ultrafast recovery diodeFeatures and benefitsDO-15DO-41KK■ Very low conduction lossesSTTH1R02QSTTH1R02■ Negligible switchin ..
STA530
4X30W STEREO BASH POWER AMPLIFIER
1/17
STA530February 2003 MONOCHIP BRIDGE QUAD CONFIGURABLE
AMPLIFIER OPTIMIZED FOR BASH®
ARCHITECTURE 4 X 50W OUTPUT POWER @ RL = 8 Ω,
THD = 10% or (2 x 50W @ 8 Ω + 1 x 100W @
4Ω) or (2 x 100W @ 4 Ω) PRECISION RECTIFIERS TO DRIVE THE
BUCK REGULATOR ON-OFF SEQUENCE/ TIMER WITH MUTE
AND STANDBY PROPORTIONAL OVER POWER OUTPUT
CURRENT TO LIMIT THE BUCK REGULATOR ABSOLUTE POWER BRIDGE OUTPUT
TRANSISTOR POWER PROTECTION ABSOLUTE OUTPUT CURRENT LIMIT INTEGRATED THERMAL PROTECTION POWER SUPPLY OVER VOLTAGE
PROTECTION FLEXIWATT POWER PACKAGE WITH 27 PIN
BASH® LICENCE REQUIRED
DESCRIPTIONThe STA530 is a BASH® power amplifier where
BASH® means “High Efficiency”.
TARGET SPECIFICATION4 X 50W STEREO POWER AMPLIFIER
BLOCK DIAGRAM
STA530 2/17
DESCRIPTION (continued)In fact it's permits to build a BASH® architecture amplifier adding only few external components and a variable
Buck regulator tracking the audio signal. Notice that normally only one Buck regulator is used to supply a mul-
tichannel amplifiers system , therefore most of the functions implemented in the circuit have a summing output
pin.
The signal circuits are biased by fixed negative and positive voltages referred to Ground. Instead the final stag-
es of the output amplifiers are supplied by two external voltages that are following the audio signal . In this way
the headroom for the output transistors is kept at minimum level to obtain a high efficiency power amplifier.
The circuit contains all the blocks to build a configurable four channel amplifier.
The tracking signal for the external Buck regulator is generated from the Absolute Value Block (AVB) that rec-
tifies the audio signal. The outputs of these blocks are decoupled by a diode to permit an easy sum of this signal
for the multichannel application. The gain of the stage AVB is equal to 70 (+36.9 dB). A sophisticated circuit
performs the output transistor power detector that , with the buck regulator, reduces the power supply voltage .
Moreover, a maximum current output limiting and the over temperature sensor have been added to protect the
circuit itself. The external voltage applied to the STBY/MUTE pin forces the two amplifiers in the proper condi-
tion to guarantee a silent turn-on and turn-off.
ABSOLUTE MAXIMUM RATINGSNotes:1. VCD- must not be more negative than -Vs
THERMAL DATA
3/17
STA530
OPERATING RANGE
PIN CONNECTION
NOTE
Slug connected to PINs No. 1 & 27
STA530 4/17
PIN CONNECTION
5/17
STA530
ELECTRICAL CHARACTERISTCS (Test Condition: Vs+ = 25V, Vs- = -25V, VCD+ = 15V, VCD- = -15V, RL =8Ω, external components at the nominal value f = 1KHz, Tamb = 25°C unless otherwise specified)
STA530 6/17
ELECTRICAL CHARACTERISTCS (continued)
7/17
STA530
FUNCTIONAL DESCRIPTIONThe circuit contains all the blocks to build a configurable four channel amplifier.
In fact, only driving properly the TRK_2 (and TRK_4) pins, it’s possible to change the chip configuration: 50 Watt x 4 50 Watt x 2 + 100 Watt x1 (TRK_2/Par1&2 or TRK_4/Par3&4 at -Vs) 100 Watt x 2 (TRK_2/Par1&2 and TRK_4/Par3&4 at -Vs)
Each single channel is based on the Output Bridge Power Amplifier, and its protection circuit. Moreover, a sig-
nal rectifier are added to complete the circuit.
The operation modes are driven by The Turn-on/off sequence block. In fact the IC can be set in three states by
the Stby/mute pin:
STANDBY ( Vpin < 0.8V), MUTE (1.6V < Vpin < 2.5V), and PLAY (Vpin > 4V).
In the Standby mode all the circuits involved in the signal path are uninhabited, instead
in Mute mode the circuits are biased but the Speakers Outputs are forced to ground potential.
These voltages can be get by the external RC network connected to Stby/Mute pin.
The same block is used to force quickly the I.C. In standby mode or in mute mode when the I.C. dangerous
condition has been detected. The RC network in these cases is used to delay the Normal operation restore.
The protection of the I.C. are implemented by the Over Temperature, Unbalance Ground, Output Short circuit,
Under voltage, and output transistor Power sensing as shown in the following table:
Table 1. Protection Implementation
ABSOLUTE VALUE BLOCKThe absolute value block rectifies the signal to extract the control voltage for the external Buck regulator. The
output voltage swing is internally limited, the gain is internally fixed to 70.
The input impedance of the rectifier is very high , to allow the appropriate filtering of the audio signal before the
rectification.
STA530 8/17
OUTPUT BRIDGEThe Output bridge amplifier makes the single-ended to Differential conversion of the Audio signal using two
power amplifiers, one in non-inverting configuration with gain equal to 10 and the other in inverting configuration
with unity gain. To guarantee the high input impedance at the input pins, PWR_Inp1....4, the second amplifier
stages are driven by the output of the first stages respectively.
In 60W x2 channel configuration the "slave" inputs (INPUT 2/4) must be connected to GND.
POWER PROTECTIONTo protect the output transistors of the power bridge a power detector is implemented (fig 1).
The current flowing in the power bridge and the voltage drop on the relevant power (Vds) are internally mea-
sured. These two parameters are converted in current and multiplied: the resulting current , Ipd, is proportional
to the instantaneous dissipated power on the relevant output transistor. The current Ipd is compared with the
reference current Ipda, if bigger (dissipated power > 18W) a current, Iprot(PD), is supplied to the Protection pin.
The aim of the current Iprot is to reduce the reference voltage for the Buck regulator supplying the power stage
of the chip, and than to reduce the dissipated power. The response time of the system must be less than
200 μSec to have an effective protection. As further protection, when Ipd reaches an higher threshold (when the
dissipated value is higher then 30W) the chip is shut down, forcing low the Stby/Mute pin, and the turn on se-
quence is restarted. The above description is relative for each channel in 4x30W configuration.
Figure 1. Power Protection Block Diagram
9/17
STA530In fig. 2 there is the power protection strategy pic-
tures. Under the curve of the 18W power, the chip is
in normal operation, over 30W the chip is forced in
Standby. This last status would be reached if the
Buck regulator does not respond quikly enough re-
ducing the stress to less than 30W.
The fig.3 gives the protection current, Iprot(PD), be-
havior. The current sourced by the pin Prot follows
the formula:
(for each channel)
for Pd < Pd_av_th the Iprot(PD)= 0.
Figure 2. Power protection threshold
Figure 3. Protection current behaviour Iprot (PD)
CURRENT PROTECTIONThe chip is also protected by a current detection.
The current ILOAD is compared with the reference
current ILIMP, if bigger (ILOAD> 4,5 A)a current Ip-
rot(IL), is supplied to the Protection pin.
As further protection, when ILOAD reaches an higher
threshold (5 A) the chip is shut down, forcing low the
Stby/Mute pin, and the turn on sequence is restarted.
The above description is relative for each channel in
4x30W configuration.
The fig.4 gives the protection current, Iprot(IL), be-
havior. The current sourced by the pin Prot follows
the formula: (for each channel)
for IlLOAD < Iict,s the Iprot(IL) = 0.
For the parallel channel Iprot is double.
The chip is also shut down in the following conditions:
When the average junction temperature of the chip
reaches 150°C.
When the ground potential differ from more than 5V
from the half of the power supply voltage, ((CD+)-
(CD-))/2
When the sum of the supply voltage |Vs+| + |Vs-|
<20V
The output bridge is muted when the average junc-
tion temperature reaches 130°C.
Figure 4. Protection current behaviour Iprot (IL) prot PD()d P d_av_th)–( 5104–⋅⋅
1.25V--------- --------------- --------------- ---------------- ------------≡ protIL() LOADIicts,)–(
2500------------- --------------- ------------≡
