SA57031-XX Datasheet, PDF (9/13 Pages) NXP Semiconductors – Micropower 150 mA, low-noise, low dropout linear regulator with on/off

Philips Semiconductors
Micropower 150 mA, low-noise, low dropout linear
regulator with on/off
Product data
SA57031-XX
APPLICATION INFORMATION
The following points have to be kept in mind for good performance
while using these devices.
Input Capacitor
An input capacitor of 2.2 µF is required between the SA57031 input
pin and the circuit ground. This capacitor must be located as close
as possible to the VI or GND pin (not more than 1 cm away from the
pin) and returned to a clean analog ground. Any good quality
ceramic, tantalum, or film capacitor will work.
Output Capacitor
Phase compensation is used for securing stable operation even if
the load current varies. For this reason, an output capacitor with
good frequency characteristics is needed. Set it as close to the
circuit as possible and make the wiring as short as possible. The
value of the output capacitance has to be at least 2.2µF and has to
have B-type temperature characteristics.
ON/OFF (Chip Enable) Pin
The ON/OFF pin must be actively terminated, not floating. If the
function is not needed, the pin should be tied to VI to permanently
enable the device.
Line Impedance of VI and GND
The VI and GND lines should be sufficiently wide to minimize
impedance. If the impedance of these lines is high, there is a chance
to pick up noise or malfunction.
ON/OFF PIN MUST BE ACTIVELY TERMINATED
ON
OFF
GND
A2
B2
SA57031-XX
A1
B1
V_I
C_I
2.2 µF
+ DC
– 2.0 V TO 6.0 V
R_LOAD
V_O
A
V
C_O
C_O = 2.2 mF for V_O = 2.5 to 5.0 V
C_O = 4.7 mF for V_O = 1.8 to 2.5 V
Figure 17. Typical application circuit.
SA00632
2003 Jun 23
9