l4995r STMicroelectronics, l4995r Datasheet - Page 6

• Manufacturer Part Number: l4995r
• Description: 5v, 500ma Low Drop Voltage Regulator
• Manufacturer: STMicroelectronics

Block diagrams and pins descriptions
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Figure 3.
Table 2.
name
Gnd
Gnd
Vcw
Res
Pin
Vcr
NC
En
PowerSSO-12
V
Block diagram of L4995R
Pins descriptions
VEn
S
2, 4, 8
pin #
Is
1
3
5
6
7
-
Vs
Vcr
Vcr
PowerSSO-24
3, 5, 6, 9, 11
13, 14, 15
19, 20, 21
22, 23, 24
16, 17, 18
pin #
1, 12
Reference
2
Voltage
Start up
Enable input (L4995 and L4996A only, otherwise not
connected).
If high regulator, watchdog and reset are operating. If
low regulator, watchdog and reset are shut down.
Connect to Vs if not used.
Not connected.
Ground reference.
Ground (these pins are to be connected to a heat
spreader electrically grounded).
Reset output.
It is pulled down when output voltage goes below Vo_th
or frequency at Wi is too low. Leave floating if not used.
Reset timing adjust.
A capacitor between Vcr pin and gnd. sets the reset
delay time (trd). Leave floating if Reset is not used.
Watchdog timer adjust (L4995 only, otherwise not
connected).
A capacitor between Vcw pin and gnd. sets the time
response of the watchdog monitor.
GND
100mV + _
Low Voltage
Reset
1.25V
Function
V
Vo
Vos
Res
Res
Vo
Io
L4995