CS8127 Cherry Semiconductor Corporation, CS8127 Datasheet

no-image

CS8127

Manufacturer Part Number
CS8127
Description
5V Linear Controller/Driver
Manufacturer
Cherry Semiconductor Corporation
Datasheet
Rev. 2/12/99
Pwr Gnd
Ref Gnd
The CS8127 contains all the necessary
control circuitry to implement a 5V lin-
ear regulator. An external pass device is
used to produce superior performance
compared to conventional monolithic
regulators. The CS8127 with a TIP42
PNP transistor typically provides a
100mV dropout voltage at 500mA,
increasing to 350mV at 3A. Quiescent
current at 500mA is only 5mA.
Monolithic regulators cannot approach
these figures because their power tran-
sistors do not provide the high beta and
excellent saturation characteristics at
high currents. The CS8127 is compatible
with a wide variety of external transis-
tors, allowing flexibility for thermal,
space, and cost management.
The CS8127 includes thermal shutdown,
externally programmable current limit,
and over-voltage shutdown, making it
suitable for use in automotive and
switching regulator post regulator appli-
cations. An optional external RC filter
added to the CS8127 supply lead pro-
vides EMC hardening in addition to the
on-chip EMC hardening. The SENSE
Delay
V
IN
Regulated Supply
for Circuit Bias
REGULATOR
PRE-
10mA
Delay
Current
V
IC
Power
Gnd
+
IC
Reference
Gnd
-
dis
Discharge
Latching
5V Linear Controller/Driver
Q S
R
Description
Reference
Bandgap
Shutdown
Thermal
+
-
Block Diagram
Delay
Comparator
Reset
Comparator
1.25V
+
-
-
lead allows remote sensing of the output
voltage for improved regulation.
An active microprocessor RESET func-
tion is included on-chip with externally
programmable delay time. During
power-up, or after detection of any error
in the regulated output, the RESET lead
will remain in the low state for the dura-
tion of the delay. Types of errors include
short circuit, low input voltage, over-
voltage shutdown, thermal shutdown,
or others that cause the output to
become unregulated. This function is
independent of the input voltage and
will function correctly with an output
voltage as low as 1V. Hysteresis is
included in both the reset and delay
comparators for noise immunity and to
prevent oscillations. A latching dis-
charge circuit is used to discharge the
delay capacitor, even when triggered by
a relatively short fault condition. This
circuit improves upon the commonly
used SCR structure by providing
improved noise immunity and full
capacitor discharge (0.2V typ).
Error
Amp
CS8127
Shutdown
Voltage
Over
1
50mA
Sense
PULLUP
V
RESET
OUT
2000 South County Trail, East Greenwich, RI 02818
RESET
Sense
Delay
Tel: (401)885-3600 Fax: (401)885-5786
Cherry Semiconductor Corporation
V
Web Site: www.cherry-semi.com
IN
Externally Set Delay for
Reset
60V Peak Transient
Capability
Internal Thermal
Overload Protection
3% Output Accuracy
Active RESET
Noise Immunity
On Chip EMC Hardening
Protection Incorporated
Externally Set Current
Limit
Email: info@cherry-semi.com
Package Options
1
2
3
4
8L SO & 8L PDIP
Features
A
8
7
6
5
¨
Pwr Gnd
Pullup
Ref Gnd
V
Company
OUT

Related parts for CS8127

CS8127 Summary of contents

Page 1

... An optional external RC filter added to the CS8127 supply lead pro- vides EMC hardening in addition to the on-chip EMC hardening. The SENSE Block Diagram Pwr Gnd ...

Page 2

Power Dissipation.............................................................................................................................................Internally Limited Input Voltage ..................................................................................................................................................................Ð0.3V, 26V Transient Input Voltage ............................................................................................................................................................60V Output Current ...............................................................................................................................................Externally Limited ESD Susceptibility (Human Body Model)..............................................................................................................................2kV Junction Temperature ............................................................................................................................................Ð45¡C to 150¡C Storage Temperature..............................................................................................................................................Ð55¡C to 150¡C Lead Temperature Soldering Wave Solder (through hole styles only) .....................................................................................10 sec. ...

Page 3

PACKAGE LEAD # 8L SO & PDIP Typical Performance Characteristics (per Test Circuit) Temperature Performance of V OUT 5.02 I =500mA OUT 5.01 5.00V @ 25°C 5 4.99 4.98 4.97 4.96 4.95 ...

Page 4

... V RL Delay DTC V DTD The CS8127 function is very precise, has hysteresis RESET on both the RESET and Delay comparators, a latching Delay capacitor discharge circuit, and operation down to 1V. The reset circuit output is an open collector type with ON and OFF parameters as specified. The reset output NPN transistor is controlled by the Low Voltage Inhibit and Reset Delay circuits (see Block Diagram) ...

Page 5

... To optimize ther- mal shutdown, board design should minimize the differ- ence in temperature of the CS8127 and the pass device. External Component Selection External Pass Device - Select a pass device that will deliv- er the desired output current, withstand the maximum expected input voltage, and dissipate the resulting power ...

Page 6

... REF: JEDEC MS-001 1.27 (.050) 0.40 (.016) REF: JEDEC MS-012 Ordering Information Part Number Description CS8127YN8 8 Lead PDIP CS8127YD8 8 Lead SO Narrow CS8127YDR8 8 Lead SO Narrow (tape & reel) Rev. 2/12/99 Package Specification Thermal Data D English RQ Min Max Min JC RQ 9.02 .400 ...

Related keywords