LT1933ES6#PBF Linear Technology, LT1933ES6#PBF Datasheet - Page 9

• Manufacturer Part Number: LT1933ES6#PBF
• Description: IC, STEP-DOWN REGULATOR, 6-TSOT-23
• Manufacturer: Linear Technology

Specifications of LT1933ES6#PBF

• Primary Input Voltage: 36V
• No. Of Outputs: 1
• Output Current: 600mA
• No. Of Pins: 6
• Operating Temperature Range: -40°C To +85°C
• Supply Voltage Range: 3.6V To 36V
• Switching Frequency Max: 600kHz
• Msl: MSL 1 - Unlimited
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

APPLICATIONS INFORMATION
switching current into a tight local loop, minimizing EMI.
A 2.2μF capacitor is capable of this task, but only if it is
placed close to the LT1933 and the catch diode; see the
PCB Layout section. A second precaution regarding the
ceramic input capacitor concerns the maximum input
voltage rating of the LT1933. A ceramic input capacitor
combined with trace or cable inductance forms a high
quality (under damped) tank circuit. If the LT1933 circuit
is plugged into a live supply, the input voltage can ring to
twice its nominal value, possibly exceeding the LT1933’s
voltage rating. This situation is easily avoided; see the Hot
Plugging Safely section.
Output Capacitor
The output capacitor has two essential functions. Along
with the inductor, it fi lters the square wave generated
by the LT1933 to produce the DC output. In this role it
determines the output ripple, and low impedance at the
switching frequency is important. The second function
is to store energy in order to satisfy transient loads and
stabilize the LT1933’s control loop.
Table 2.Inductor Vendors
Vendor
Panasonic
Kemet
Sanyo
Murata
AVX
Taiyo Yuden
Phone
[phone]
[phone]
[phone]
[phone]
[phone]
URL
www.panasonic.com
www.kemet.com
www.sanyovideo.com
www.murata.com
www.avxcorp.com
www.taiyo-yuden.com
Ceramic capacitors have very low equivalent series re-
sistance (ESR) and provide the best ripple performance.
A good value is
where C
in mind that a ceramic capacitor biased with V
have less than its nominal capacitance. This choice will
provide low output ripple and good transient response.
Transient performance can be improved with a high value
capacitor, but a phase lead capacitor across the feedback
resistor R1 may be required to get the full benefi t (see the
Compensation section).
High performance electrolytic capacitors can be used for
the output capacitor. Low ESR is important, so choose one
that is intended for use in switching regulators. The ESR
should be specifi ed by the supplier, and should be 0.1Ω
or less. Such a capacitor will be larger than a ceramic
capacitor and will have a larger capacitance, because the
capacitor must be large to achieve low ESR. Table 2 lists
several capacitor vendors.
C
OUT
Part Series
Ceramic,
Polymer,
Tantalum
Ceramic,
Tantalum
Ceramic,
Polymer,
Tantalum
Ceramic
Ceramic,
Tantalum
Ceramic
= 60/V
OUT
is in μF . Use X5R or X7R types, and keep
OUT
Comments
EEF Series
T494, T495
POSCAP
TPS Series
LT1933
OUT
1933fe
9
will