MC33998_06 Datasheet, PDF (1/20 Pages) Freescale Semiconductor, Inc – Switching Power Supply with Linear Regulators

Freescale Semiconductor
Technical Data
Document Number: MC33998
Rev. 2.0, 8/2006
Switching Power Supply with
Linear Regulators
33998
The 33998 is a medium-power, multi-output power supply
integrated circuit that is capable of operating over a wide input
voltage range, from 6.0 V up to 26.5 V with 40 V transient capability.
It incorporates a sensorless current mode control step-down
switching controller regulating directly to 5.0 V. The 2.6 V linear
regulator uses an external pass transistor to reduce the 33998 power
dissipation. The 33998 also provides a 2.6 V linear standby regulator
and two 5.0 V sensor supply outputs protected by internal low-
resistance LDMOS transistors.
There are two separate enable pins for the main and sensor supply
outputs and standard supervisory functions such as resets with
power-up reset delay.
The 33998 provides proper power supply sequencing for
advanced microprocessor architectures such as the MPC5xx and
683xx microprocessor families.
SWITCHING REGULATOR
DW SUFFIX
EG SUFFIX (PB-FREE)
98ASB42344B
24-PIN SOICW
Features
ORDERING INFORMATION
• Operating Voltage Range 6.0 V up to 26.5 V (40 V transient)
• Step-Down Switching Regulator Output V_DDH = 5.0 V @
1400 mA (total)
• Linear Regulator with External Pass Transistor V_DDL = 2.6 V @
400 mA
Device
MC33998DW/R2
MCZ33998EG/R2
Temperature
Range (T_A)
-40°C to 125°C
Package
24 SOICW
• Low-Power Standby Linear Regulator V_KAM = 2.6 V @ 10 mA
• Two 5.0 V @ 200 mA (typical) Sensor Supplies V_REF Protected
Against Short-to-Battery and Short-to-Ground with Retry Capability
• Undervoltage Shutdown on the V_DDL, V_DDH Outputs with Retry Capability
• Reset Signals
• Power-Up Delay
• Enable Pins for Main Supplies (EN) and Sensor Supplies (SNSEN)
• Power Sequencing for Advanced Microprocessor Architectures
• Pb-Free Packaging Designated by Suffix Code EG
33998
KA_VPWR
VSW
VPWR
VDDH
5.0 V
VDDH
5.0 V
VREF1
DRVL
5.0 V
VREF2
FBL
EN
SNSEN
GND
VKAM
PWROK
VKAMOK
MCU
VDDL
2.6 V
VKAM
2.6 V
Figure 1. 33998 Simplified Application Diagram
Freescale Semiconductor, Inc. reserves the right to change the detail specifications, as
may be required, to permit improvements in the design of its products.
© Freescale Semiconductor, Inc., 2007. All rights reserved.