33730_10 Datasheet, PDF (11/26 Pages) Freescale Semiconductor, Inc – Switch Mode Power Supply with Multiple Linear Regulators

FUNCTIONAL DESCRIPTION
INTRODUCTION
FUNCTIONAL DESCRIPTION
INTRODUCTION
The 33730 multi-output power supply integrated circuit
addresses the system power supply needs for applications
using the Freescale 32-bit microcontroller family architecture.
FUNCTIONAL PIN DESCRIPTION
HARDWARE RESET TIMER (HRT)
This pin is the hardware reset timer input, which provides
delays for the Reset outputs. This delay is programmed by an
external resistor to GND.
VDDL REGULATOR BASE DRIVE (VDDL_B)
VDDL linear regulator base drive. This output supplies
current into the base of the regulator external pass NPN
transistor.
VKAM RESET (RSTKAM)
This pin is an open drain reset output monitoring the V_KAM
supply to the microprocessor. This output is actively pulled
low when the VKAM output voltage falls below its reset
threshold level.
VDDH RESET (RSTH)
This pin is an open drain reset output monitoring the
VDDH regulator. This output is actively pulled low when the
VDDH output voltage falls below its reset lower threshold
level or when the VDDH output voltage exceeds its reset
upper threshold level
VDDL RESET (RSTL)
This pin is an open drain reset output monitoring the VDDL
regulator. This output is actively pulled low when the VDDL
output voltage falls below its reset threshold level.
VDD3 RESET (RST3)
This pin is an open drain reset output monitoring the VDD3
regulator. This output is actively pulled low when the VDD3
output voltage falls below its reset threshold level.
VREF OUTPUT 2 (VREF2)
This pin is output of the protected supply VREF2. This
output supplies sensors outside of the electronic control
module and therefore it is protected against a battery short
and short to -1.0 V. This pin is supplied from the V_DDH
through the internal protection FET.
VDDL REGULATOR (VDDL)
This pin is the V_DDL regulator output feedback pin. The
emitter of VDDL regulator external NPN pass transistor is
connected to this pin.
VDDH REGULATOR (VDDH)
This pin is the 5.0 V output feedback pin of the buck
regulator. This pin is also a power input for the protected
outputs VREF1 and VREF2.
VREF OUTPUT 1 (VREF1)
This pin is output of the protected supply VREF1. This
output supplies sensors outside of the electronic control
module and therefore it is protected against short battery and
short to -1.0 V. This pin is supplied from the V_DDH through the
internal protection FET.
REGULATOR HOLD ON (REGON)
Regulator Hold On input control pin. The 33730 can be
enabled or kept in the Normal operational mode by holding
this pin high. This is a 5.0 V logic input.
VIGN STATUS (IGN_ON)
This open drain output signals the status of the VIGN pin.
This logic output is actively pulled low when the VIGN control
input is pulled high.
COMPENSATION (VCOMP)
This pin provides switching pre-regulator compensation
network. It is the output of the switching regulator error
amplifier.
INVERTING INPUT (INV)
This pin is the inverting input of the switching regulator
error amplifier.
FREQUENCY ADJUSTMENT (FREQ)
This is the frequency adjustment input of the switching
regulator. The operating frequency of the switching regulator
can be programmed by an external resistor from this pin to
ground.
PROGRAMMING PIN 1 (P1)
Programming Pin 1 for the VDD3, VDDL, and VKAM
reference voltage. The output voltage of the VDD3, VDDL
and VKAM regulators can be programmed by the P1, P2, and
P3 pins (see Table 6).
Analog Integrated Circuit Device Data
Freescale Semiconductor
33730
11