CS8127 Cherry Semiconductor Corporation, CS8127 Datasheet - Page 4

• Manufacturer Part Number: CS8127
• Description: 5V Linear Controller/Driver
• Manufacturer: Cherry Semiconductor Corporation

The CS8127
on both the
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).
This circuit monitors output voltage, and when output
voltage is below V
be in the ON (saturation) state. When the output voltage is
above V
to go into the OFF state if allowed by the reset Delay cir-
cuit.
RTH
(3)
, this circuit permits the reset output transistor
RESET
RESET
RESET
Low Voltage Inhibit Circuit
Delay
RTL
V
V
V
V
V
and Delay comparators, a latching
function is very precise, has hysteresis
OUT
DTC
DTD
RTH
RT
, causes the reset output transistor to
L
V
V
RL
V
RH
DH
RESET Circuit Functional Description
RESET Circuit Waveform
(1)
T
D
(2)
4
This circuit provides a programmable (by external capaci-
tor) delay on the
vides source current to the external delay capacitor only
when the Low Voltage Inhibit circuit indicates that output
voltage is above V
current to ground (used to discharge the Delay capacitor).
The discharge current is latched ON when the output volt-
age falls below V
charged anytime the output voltage falls out of regulation,
even for a short period of time. This feature ensures a con-
trolled
of an error condition. The circuit allows the
put transistor to go to the OFF (open) state only when the
voltage on the Delay lead is higher than V
(2)
RESET
pulse is generated following the detection
RTL
RESET
RTH
RESET Delay Circuit
. The Delay capacitor is fully dis-
. Otherwise, the Delay lead sinks
output lead. The Delay lead pro-
(1) = No Delay Capacitor
(2) = With Delay Capacitor
(3) = Max: RESET Voltage (1.0V)
DTC
RESET
.
V
DIS
out-