CS8141YDPSR7 ON Semiconductor, CS8141YDPSR7 Datasheet - Page 7

• Manufacturer Part Number: CS8141YDPSR7
• Description: IC REG LDO LIN 500MA 5V D2PAK-7
• Manufacturer: ON Semiconductor

Specifications of CS8141YDPSR7

• Regulator Topology: Positive Fixed
• Voltage - Output: 5V
• Voltage - Input: 7 ~ 26 V
• Voltage - Dropout (typical): 1.25V @ 500mA
• Number Of Regulators: 1
• Current - Output: 500mA
• Current - Limit (min): 700mA
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: TO-263-7, D²Pak (7 leads + Tab), TO-263CA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: CS8141YDPSR7OS

at which the circuit ceases to regulate against further
reduction in input voltage. Measured when the output
voltage has dropped 100 mV from the nominal value
obtained at 14 V input, dropout voltage is dependent upon
load current and junction temperature.
terminals with respect to ground.
change in the input voltage. The measurement is made under
conditions of low dissipation or by using pulse techniques
circuitry and three logic control functions that allow a
microprocessor to control its own power supply. The CS8140
is designed for use in automotive, switch mode power supply
post regulator, and battery powered systems.
noise, low drift, 5.0 V ±4.0% precision output voltage with
low dropout voltage (1.25 V @ I
quiescent current (7.0 mA @ I
short circuit, thermal, and overvoltage protection make it
possible to use this regulator in particularly harsh operating
environments.
(WDI) from the microprocessor or other signal source.
When the signal frequency moves outside externally
programmable window limits, a RESET signal is generated
(RESET). An external capacitor (C
watchdog window frequency limits as well as the power on
reset (POR) and RESET delay.
conditions: the watchdog signal moves outside of its preset
limits; the output voltage drops out of regulation by more
than 4.5%; or the IC is in its power up sequence. The RESET
signal is independent of V
1.0 V.
controls the regulator’s power consumption. The CS8140’s
output stage and its attendant circuitry are enabled by setting
the ENABLE lead high. The regulator goes into sleep mode
when the ENABLE lead goes low and the watchdog signal
moves outside its preset window limits. This unique
combination of control functions in the CS8140 gives the
microprocessor control over its own power down sequence:
i.e. it gives the microprocessor the flexibility to perform
housekeeping functions before it powers down.
that the CS8141 only responds to input signals (WDI) which
are below the preset watchdog frequency threshold.
Dropout Voltage: The input−output voltage differential
Input Voltage: The DC voltage applied to the input
Line Regulation: The change in output voltage for a
The CS8140 is a 5.0 V Watchdog Regulator with protection
Basic regulator performance characteristics include a low
The Watchdog logic function monitors an input signal
The RESET function is activated by any of three
In conjunction with the Watchdog, the ENABLE function
The CS8141 has the same features as the CS8140, except
IN
and reliable down to V
OUT
OUT
= 500 mA). On board
DELAY
= 500 mA) and low
) programs the
DEFINITION OF TERMS
CIRCUIT DESCRIPTION
CS8140, CS8141
http://onsemi.com
OUT
=
7
such that the average chip temperature is not significantly
affected.
change in load current at constant chip temperature.
that does not contribute to the positive load current. The
regulator ground lead current.
ripple voltage to the peak−to−peak output ripple voltage.
output.
Precision Voltage Reference
band gap voltage reference in the IC. By adding an error
amplifier into the feedback loop, the output voltage is
maintained within ±4.0% over temperature and supply
variation.
Output Stage
provides 500 mA (min) of output current while maintaining
a low drop out voltage (1.25 V) and drawing little quiescent
current (7.0 mA).
output stage which in turn improves the IC’s efficiency by
preventing excess current from being used and dissipated by
the IC.
Output Stage Protection
circuit and thermal runaway conditions (Figure 15).
output shuts down. This response protects the internal
circuitry and enables the IC to survive unexpected voltage
transients.
through the NPN pass transistor is monitored. Feedback
Figure 14. Composite Output Stage of the CS8140/1
Load Regulation: The change in output voltage for a
Quiescent Current: The part of the positive input current
Ripple Rejection: The ratio of the peak−to−peak input
Current Limit: Peak current that can be delivered to the
The regulated output voltage depends on the precision
The composite PNP−NPN output structure (Figure 14)
The NPN pass device prevents deep saturation of the
The output stage is protected against overvoltage, short
If the input voltage rises above 30 V (e.g. load dump), the
Using an emitter sense scheme, the amount of current
VOLTAGE REFERENCE AND OUTPUT CIRCUITRY
V
IN
V
OUT