MC33997DW Freescale Semiconductor, MC33997DW Datasheet - Page 3

• Manufacturer Part Number: MC33997DW
• Description: IC SWITCH 3.3/5V SUPPLY 24-SOIC
• Manufacturer: Freescale Semiconductor

Specifications of MC33997DW

• Applications: Switching Power Supply, Microprocessor
• Voltage - Input: 6 ~ 26.5 V
• Number Of Outputs: 5
• Voltage - Output: 3.3V, 5V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-SOIC (7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Table 1. 33997 Pin Function Definition
Analog Integrated Circuit Device Data
Freescale Semiconductor
Pin Number
17 – 20
5 – 8
10
11
12
13
14
15
16
21
22
1
2
3
4
9
KA_VPRW
Pin Name
VKAMOK
PWROK
VFREF2
SNSEN
VREF1
VPWR
VSUM
VDDH
CRES
DRVL
FBKB
GND
VSW
GND
FBL
Keep-Alive Output Monitoring. This pin is an "open-drain" output that will be used with a discrete pull-up resistor
to VKAM. When the supply voltage to the 33997 is disconnected or lost, the VKAMOK signal goes low.
Keep Alive Power Supply Pin. This supply pin is used in modules that have both direct battery connections and
ignition switch activated connections.
Reservoir Capacitor. This pin is tied to an external "reservoir capacitor" for the internal charge pump.
Power Supply Pin. Main power input to the IC. This pin is directly connected to the switching regulator power
MOSFET. In automotive applications this pin must be protected against reverse battery conditions by an
external diode.
Ground of the integrated circuit.
Internal P-Channel Power MOSFET Drain. VSW is the "switching node" of the voltage buck converter. This pin
is connected to the VPWR pin by an integrated p-channel MOSFET.
Power OK Reset Pin. This pin is an "open-drain" output that will be used with a discrete pull-up resistor to V
V
down.
Step-Down Switching Regulator Feedback Pin. The FBKB pin is the V
regulator.
Error Amplifier "Summing Node". The VSUM pin is connected to the inverting input of the error amplifier. This
node is also the "common" point of the integrated feedback resistor divider.
Drive for V
linear post regulator. The collector of the VDDL pass transistor is connected to V
pass transistor is BCP68.
Feedback for V
linear post regulator.
VDDH is an input supply pin providing power for the buffered sensor supplies and the drive circuitry for the 3.3 V
linear power regulator. The VDDH pin is supplied from the switching regulator output, capable of providing
5.0 V @ 1400 mA total output current.
Sensor Supply #2 Output. The VFREF2 pin is sensor supply output #2.
Ground of the integrated circuit.
Sensor Supply #1 Output. The VREF1 pin is sensor supply output #1.
Sensor Supply Enable Input. The SNSEN pin is an input, which enables the V
allows the control module hardware / software to shut down the sensor supplies.
DDH
, or V
DDL
DDL
(3.3 V) Regulator. The DRVL pin drives the base of an external NPN pass transistor for the V
. When either V
DDL
KA_VPWR
VKAMOK
PWROK
Figure 3. 33997 Pin Connections
(3.3 V) Regulator. The FBL pin is the voltage feedback sense signal from the V
VPWR
VSUM
CRES
FBKB
VSW
GND
GND
GND
GND
PIN CONNECTIONS
DDH
1
2
3
4
5
6
7
8
9
10
11
12
or V
DDL
24
23
22
21
20
19
18
17
16
15
14
13
output voltage goes out of the regulation limits this pin is pulled
Definition
VKAM
EN
SNSEN
VREF1
GND
GND
GND
GND
VREF2
VDDH
FBL
DRVL
DDH
feedback signal for the switching
REF1
DDH
. An example of a suitable
and V
PIN CONNECTIONS
REF2
supplies. It
DDL
(3.3 V)
KAM
33997
DDL
,
3