lp2985-28d NXP Semiconductors, lp2985-28d Datasheet - Page 9

• Manufacturer Part Number: lp2985-28d
• Description: Lp2985-xx Micropower 150 Ma Low Noise, Low Dropout Linear Regulator
• Manufacturer: NXP Semiconductors

Philips Semiconductors
APPLICATION INFORMATION
The following points have to be kept in mind for good performance
while using these devices:
Input Capacitor
An input capacitor of greater than 1 F is required between the
LP2985-XX input pin and the circuit ground (the amount of
capacitance may be increased without limit). This capacitor must be
located as close as possible to the V
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
TEST CIRCUITS
2003 Oct 31
Micropower 150 mA low noise,
low dropout linear regulator
SUPPLY VOLTAGE
SUPPLY VOLTAGE
OUTPUT VOLTAGE
TEST LOAD
IN
or GND pin (not more than
Figure 22. Typical application circuit, device always ON.
A
A
Figure 23. Test circuit.
1 F
1 F
1 F
1 F
V
V
9
V
V
OUT
OUT
5
1
5
1
IN
IN
value of the output capacitance must be at least 1 F and must have
good frequency characteristics is needed. Set it as close to the
circuit as possible and make the wiring as short as possible. The
B-type temperature characteristics. Also it must have the ESR
(Equivalent Series Resistance) value within the stable range shown
in the ESR versus I
ON/OFF (Chip Enable) Pin
The ON/OFF pin must be actively terminated, not floating. If the
function is not to be used, the pin should be tied to V
Line Impedance of V
The V
impedance. If the impedance of these lines is high, there is a
chance to pick up noise or malfunction.
IN
GND
GND
2
2
V
and GND lines should be sufficiently wide to minimize
ON/OFF
ON/OFF
NOISE
NOISE
4
4
A
3
3
O
plot.
IN
and GND
SL01546
SL01547
0.01 F
0.01 F
LP2985-XX
IN
.
Product data