tda3683 NXP Semiconductors, tda3683 Datasheet - Page 24

• Manufacturer Part Number: tda3683
• Description: Tda3683 Multiple Voltage Regulator With Switch And Ignition Buffer
• Manufacturer: NXP Semiconductors

Philips Semiconductors
TDA3683_2
Product data sheet
11.1 Application notes
Fig 9. Hold decoder circuit
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A ceramic capacitor of 220 nF must be connected to both supply pins to guarantee
stability over the ambient temperature range. For improved noise performance it is
also recommended to connect a standard electrolytic capacitor of 2200 F close to
the supply pins.
A ceramic capacitor of 220 nF must be connected to the storage capacitor pin when
the back-up function is not used to guarantee stability over the ambient temperature
range. There are basically no restrictions for the maximum value of the storage
capacitor, but the required value depends on the actual output currents of the three
standby regulators and the length of time that their outputs must be maintained after
the supply voltage collapsed (V
A standard electrolytic capacitor of 10 F, or more, must be connected to the output of
the power switch to guarantee stability over the ambient temperature range. A ceramic
capacitor of 100 nF can be added in parallel with the electrolytic capacitor to provide
improved HF performance.
An electrolytic capacitor of 10 F, or more, must be connected to each regulator
output to guarantee stability over the ambient temperature range. There are
restrictions concerning the maximum ESR of the electrolytic capacitors that are used;
see
ESR decreases with temperature so the worst case condition for stability (i.e.
minimum capacitance and maximum ESR) exists at low temperatures. Depending on
the specified temperature range of the radio set, some of the regulator outputs may
need low ESR type electrolytic or tantalum capacitors. A ceramic capacitor of 100 nF
can be added in parallel with the electrolytic or tantalum capacitor to provide improved
HF performance. However, in the case of the standby regulators (REG1 to REG3)
these additional ceramic capacitors should preferably not be connected very close to
the device pins to avoid stability issues.
Table
R1 to R7: Standard E12 series resistor, 5 % tolerance
T1, T3: Standard small signal NPN transistor
T2: Standard small signal PNP transistor
D1: Low forward voltage (Schottky) diode
HOLD output
REG2 output
8. Usually the nominal value of electrolytic capacitors increases and the
3.3 V
Rev. 02 — 7 October 2005
R1
18 k
R2
27 k
Multiple voltage regulator with switch and ignition buffer
P1
= V
T1
R3
2 k
R4
10 k
P2
D1
= 0 V).
temperature
prewarn
T2
R5
330 k
6.8 k
R6
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
001aaa690
T3
R7
10 k
diagnostic
TDA3683
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