pq1cz21h2z Sharp Microelectronics of the Americas, pq1cz21h2z Datasheet - Page 6

• Manufacturer Part Number: pq1cz21h2z
• Description: Dissipation Current Off-state Chopper Regulator
• Manufacturer: Sharp Microelectronics of the Americas

1. External connection
(1) Wiring condition is very important. Noise associated with wiring inductance may cause problems.
(2) High switching speed and low forward voltage type schottky barrier diode should be recommended for the catch-diode D
(3) The output ripple voltage is highly influenced by ESR(Equivalent Series Resistor)of output capacitor, and can be minimized by
(4) An inductor should not be operated beyond its maximum rated current so that it may not saturate.
(5) When voltage that is higher than V
Precautions for Use
For minimizing inductance, it is recommended to design the thick and short pattern (between large current diodos, input/output
capacitors, and terminal 1,2.) Single-point grounding (as indicated) should be used for best results.
because it affects the efficiency. Please select the diode which the current rating is at least 1.2 times greater than maximum
swiching current.
selecting Low ESR capacitor.
V
output capacitor (C
connect as the following circuit.
IN
1
is shorted to GND in normal condition, there is the case that the device is broken since the charged electric charge in
V
IN
1
PQ1CZ21H2Z
O
) flows into input side. In such case a schottly barrier diode or a silicon diode shall be recommended to
C
IN
1
PQ1CZ21H2Z
2
IN
1
, is applied to V
4
3
C-MOS or TTL
2
5
OUT
2
, there is the case that the device is broken. Especially, in case
D
L
C
O
R
R
2
1
V
O
PQ1CZ21H2Z
Load