V1/Pnp Connections - NXP Semiconductors UJA1169A User Manual

NXP Semiconductors

2.2.2 V1/PNP connections

UM11758
User manual
VIN
J5
12 V
GND
J6
Figure 2. 12 V power supply connection options
The V1 supply voltage is generated by the internal 5 V or 3.3 V regulator, depending
on the UJA1169A variant, and is intended to supply the external microcontroller. It also
determines the IO reference level.
The V1 output voltage can be accessed at pin 8 on connector J3. Decoupling capacitor
C8 is provided to stabilize the output voltage and remove noise. LED D5, connected
via resistor R9, indicates the status of V1 (on when V1 active). Jumper J7 can be used
to connect V1 to J5-03 if needed as an MCU IO reference voltage. PNP pins can be
accessed at connector J9 (see
Table 4. V1/PNP connections
UJA1169A
V1 (pin 5)
VEXCTRL (pin 15)
VEXCC (pin 6)
PNP
B (pin 4)
C (pin 5)
E (pin 1,2,3)
The internal V1 voltage regulator on the UJA1169A can deliver up to 250 mA without
the need for an external PNP transistor. However, if critical thermal requirements need
to be satisfied, it is possible to connect one or more external PNP transistors to share
the total V1 load current, and therefore also share the thermal dissipation. The PNP
transistor switches on when the load current exceeds the selected PNP activation
threshold, I , while the battery supply voltage is above the PNP activation
th(act)PNP
threshold, V . The main regulation loop inside the UJA1169A continues to handle
th(act)PNP
All information provided in this document is subject to legal disclaimers.
J8
J2
D1
Schottky
diode
C1
100 µF
Figure 7).
UJA1169Ax-EVB
J3-08 provides 3.3 V (UJA1169AF3-EVB only) or 5 V for MCU
supply
J5-03: pin V1 is connected to the IOREF signal on header J5 via
jumper J7, e.g. for the MCU IO supply
TP4
J9-01: connected to the collector of the onboard PNP transistor
UJA1169Ax-EVB
J9-03: connected to the base of the onboard PNP transistor
J9-01: connected to the collector of the onboard PNP transistor
J9-04: connected indirectly via R4, 0 Ω to emitter of the onboard
PNP transistor
Rev. 1 — 19 April 2022
UJA1169A evaluation boards
BAT (p14)
R1
1 kΩ
UJA1169A
C2
0.1 µF
D2
LED
GND
(p1,4,16,19)
UM11758
aaa-045442
© NXP B.V. 2022. All rights reserved.
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