ST2054BD ,CURRENT LIMITED POWER DISTRIBUTION SWITCHESST2054CURRENT LIMITEDPOWER DISTRIBUTION SWITCHES
ST2054BD
CURRENT LIMITED POWER DISTRIBUTION SWITCHES
1/9October 2004 80mΩ HIGH-SIDE MOSFET SWITCH 500mA CONTINUOUS CURRENT PER
CHANNEL INDEPENDENT THERMAL AND
SHORT-CIRCUIT PROTECTION WITH
OVERCURRENT LOGIC OUTPUT OPERATING RANGE FROM 2.7V TO 5.5V CMOS- AND TTL-COMPATIBLE ENABLE
INPUTS 2.5ms TYPICAL RISE TIME UNDERVOLTAGE LOCKOUT 20μA MAXIMUM STANDBY SUPPLY
CURRENT AMBIENT TEMPERATURE RANGE, 0°C TO
85°C ESD PROTECTION
DESCRIPTIONThe ST2054 power distribution switches is
intended for application where heavy capacitive
loads and short circuits are likely to be
encountered. These devices incorporate 80mΩ
N-channel MOSFET high-side power switches for
power-distribution systems that require multiple
powers switches in a single package. Each switch
is controlled by an independent logic enable input.
Gate drive is provided by an internal charge pump
designed to control the power-switch rise times
and fall times to minimize current surges during
switching. The charge pump requires no external
components and allows operation from supplies
as low as 2.7 V.
When the output load exceeds the current-limit
threshold or a short is present, these devices limit
the output current to a safe level by switching into
a constant-current mode, pulling the overcurrent
(OCx) logic output low. When continuous heavy
overloads and short circuits increase the power
dissipation in the switch, causing the junction
temperature to rise, a thermal protection circuit
shuts off the switch to prevent damage. Recovery
from a thermal shutdown is automatic once the
device has cooled sufficiently. Internal circuitry
ensures the switch remains off until valid input
voltage is present. These power-distribution
switches are designed to current limit at 0.9 A.
Table 1: Order Codes
ST2054CURRENT LIMITED
POWER DISTRIBUTION SWITCHES
Rev. 2
ST20542/9
Figure 1: Pin Configuration Table 2: Pin Description
Table 3: Absolute Maximum Ratings Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is
not implied.
Note1: All voltage are referred to GND
Table 4: Recommended Operating Condition
ST20543/9
Figure 2: Block Diagram
ST20544/9
Table 5: Power Switch Electrical Characteristics (VI = 5.5V, IO = rated current, V IEN =VI, TJ = 25°C,
unless otherwise specified.) (See Note 1)
Table 6: Enable Input ENx Characteristics (VI = 5.5V, IO = rated current, VIEN =VI, TJ = 25°C, unless otherwise specified.) (See Note 1)
Table 7: Current Limit Characteristics (VI = 5.5V, IO = rated current, VIEN =VI, TJ = 25°C, unless other-wise specified.) (See Note 1)
Table 8: Supply Current Characteristics (VI = 5.5V, IO = rated current, V IEN =VI, TJ = 25°C, unless oth-
erwise specified.) (See Note 1)
Table 9: Undervoltage Characteristics (VI = 5.5V, IO = rated current, VIEN =VI, TJ = 25°C, unless other-wise specified.) (See Note 1)
ST20545/9
Table 10: Overcurrent (OC) Characteristics (VI = 5.5V, IO = rated current, V IEN =VI, TJ = 25°C, unless
otherwise specified.) (See Note 1)
Note 1: Pulse testing techniques maintain junction temperature close to ambient temperature: thermal effect must be takes into account sep-
arately.
Note 2: Specified by design, not production tested.
Figure 3: Test Circuit
Figure 4: Waveform - Propagation Delays (f=1MHz; 50% duty cycle)
