January 1999 TOKO, Inc.
Page 1
TK732xx
CPULSE
CONTROL
GND
BASE
NOISE
BYPASS
VSENSE
IPK
VIN
TK732xx
01S
FEATURES
I
Up to 5 A Output Current Capability With External
PNP Transistor
I
Internal Short Circuit Protection
I
Excellent Load Regulation
I
CMOS/TTL-Compatible On/Off Switch
I
Internal Reverse Bias Current Protection Switch
I
Internal Thermal Shutdown
I
Broad Operating Voltage Range
I
High Impedance V
SENSE
Pin (Off Mode)
I
Continuous and Pulsed Current Modes
DESCRIPTION
APPLICATIONS
I
Battery Powered Systems
I
Cellular/Cordless Telephones
I
Radio Control Systems
I
Wireless Communications Systems
I
Portable Instrumentations
I
Portable Computers
I
Personal Digital Assistants
I
Local Area Network (LAN) Receivers
I
Lithium Ion Battery Chargers
I
Power Recovery for Microprocessors
VOLTAGE CODE
20 = 2.0 V *
22 = 2.2 V *
25 = 2.5 V
27 = 2.7 V
30 = 3.0 V
31 = 3.1 V
32 = 3.2 V
34 = 3.4 V
37 = 3.7 V
39 = 3.9 V
42 = 4.2 V
43 = 4.3 V
44 = 4.4 V
46 = 4.6 V
49 = 4.9 V
55 = 5.5 V *
11 = 11.0 V
TK732 M L
ORDERING INFORMATION
Tape/Reel Code
Temp. Code
TAPE/REEL CODE
L: Tape Left
TEMP. RANGE
C: -30 to 80 C **
Package Code
Voltage Code
Grade
* Unavailable with I Rank
PACKAGE CODE
M: SOT-23L-8
None: Standard 2%
H: High (Special) **
*
BLOCK DIAGRAM
The TK732xx is a controller IC for a low dropout voltage
regulator. The TK732xx and the external PNP power
transistor provide standard output voltages from 2 to 11 V
and output current from 100 mA to 5 A. By utilizing an
external PNP power transistor, low dropout voltage at high
current can be readily achieved. The internal electronic
switch can be controlled by TTL or CMOS logic levels. The
device is in the “on” state when the control pin is pulled to
a high logic level. A pin for a bypass capacitor, which
connects to the internal circuitry, is provided to lower the
overall output noise level.
The current limit characteristics can be configured as
continuous (constant current) or pulsed (cycling). An internal
thermal shutdown circuit limits the junction temperatures
to below 150
°
C. In the “off” mode, the output of the
regulator becomes a high impedance. This prevents the
output capacitor from being rapidly discharged for backup
to the load.
CONTROL
NOISE BYPASS
VIN
SENSOR
ON/OFF
BANDGAP
PLEAKAGE
IPK
CPULSE
BASE
VSENSE
GND
LOW DROPOUT REGULATOR