Schottky Rectifier

Introduction to Schottky Rectifier:

Schottky rectifiers have been used for over 25 years in the power supply industry. The primary advantages are very low forward voltage drop and switching speeds that approach zero time making them ideal for output stages of switching power supplies. This latter feature has also stimulated their additional use in very high frequency applications including very low power involving signal and switching diode requirements of less than 100 picoseconds. These require small Schottky devices with low capacitance.

The reverse recovery time of Schottky diodes are extremely fast (but soft) recovery characteristics. What little reverse recovery time they may exhibit is primarily dictated by their capacitance rather than minority carrier recombination as in conventional pn junction rectifiers. This characteristic provides very little reverse current overshoot when switching the Schottky from the forward conducting mode to the reverse blocking state. The combination of very "fast soft switching properties" of a Schottky can also eliminate the need for snubber circuits in many applications that may otherwise be required with fast or ultrafast rectifiers displaying abrupt recovery characteristics. These features make schottky rectifiers a very attractive choice for low parasitic switching losses.

Design considerations with Schottky devices are limited in some applications compared to pn junction rectifiers because their reverse leakage currents are many times higher. Also Schottky rectifiers have maximum rated junction temperature typically in the range of 125 oC to 175 oC, compared to the typical 200 oC for conventional pn junctions which further influences leakage current behavior.

For some applications, Schottky devices are limited in available reverse blocking voltage ratings compared to conventional pn junction rectifiers. Nevertheless with judicious selection, many applications are optimized with Schottky rectifiers and their unique operating characteristics. Schottky rectifiers seldom exceed 100 volts in their working peak reverse voltage (VRRM), since devices moderately above this rating level will result in forward voltages equal to or greater than equivalent pn junction rectifiers.

Surface Mount Devices

Part Number Package IO VRRM VF
BAT54WS SOD-323 100mA 30V 0.24~1.00V
SD107WS SOD-323 100mA 30V 0.30~0.80V
SD103AWS/BWS/CWS SOD-323 0.35A 20V~40V 0.37~0.60V
B0520WS~B0540WS SOD-323 0.5A 20V~40V 0.385V~0.510V
B5817WS~B5819WS SOD-323 1.0A 20V~40V 0.45V~0.60V
BAT42W~BAT43W SOD-123 0.2A 30V 0.40~1.00V
DSS12~DSS110 SOD-123FL 1.0A 20V~100V 0.55V~0.85V
DSS22~DSS210 SOD-123FL 2.0A 20V~100V 0.55V~0.85V
DSS32~DSS310 SOD-123FL 3.0A 20V~100V 0.55V~0.85V
B0520W~B0540W SOD-123 0.5A 20V~40V 0.385V~0.510V
B5817W~B5819W SOD-123 1.0A 20V~40V 0.45V~0.60V
FM102~FM110 SOD-123 1.0A 20V~100V 0.50V~0.85V
FM202~FM210 SOD-123 2.0A 20V~100V 0.50V~0.85V
LM5817~LM5819 DO-213AA 1.0A 20V~40V 0.45V~0.90V
BAS40 series SOT-23 0.2A 40V 0.38~1.00V
BAT54 series SOT-23 0.2A 30V 0.24V~1.00V
SM5817~SM5819 MELF (DO-213AB) 1.0A 20V~40V 0.45V~0.60V
S12~S120 SMA (DO-214AC) 1.0A 20V~200V 0.45V~0.95V
S22~S220 SMA (DO-214AC) 2.0A 20V~200V 0.55V~0.95V
S22AF~S220AF SMAF 2.0A 20V~200V 0.55V~0.95V
S32~S320 SMA (DO-214AC) 3.0A 20V~200V 0.55V~0.95V
S32AF~S320AF SMAF 5.0A 20V~200V 0.55V~0.95V
MBRA340 SMA (DO-214AC) 3.0A 40V 0.55V
S52~S520 SMA 5.0A 20V~200V 0.55V~0.95V
S52AF~S520AF SMAF 5.0A 20V~200V 0.55V~0.95V
S55L~S56L SMA (DO-214AC) 5.0A 50V~60V 0.55V
SB22~SB220 SMB (DO-214AA) 2.0A 20V~200V 0.55V~0.95V
SB32~SB320 SMB (DO-214AA) 3.0A 20V~200V 0.55V~0.95V
SB52~SB520 SMB (DO-214AA) 5.0A 20V~200V 0.55V~0.95V
SS32~SS320 SMC (DO-214AB) 3.0A 20V~200V 0.55V~0.95V
SS52~SS520 SMC (DO-214AB) 5.0A 20V~200V 0.55V~0.95V
SS62~SS620 SMC (DO-214AB) 6.0A 20V~200V 0.55V~0.90V
SS82~SS820 SMC (DO-214AB) 8.0A 20V~200V 0.55V~0.85V
SS102~SS1020 SMC (DO-214AB) 10.0A 20V~200V 0.65V~0.85V
SDF22S~SDF210S DFS 2.0A 20V~100V 0.55V~0.85V
ABS32~ABS310 ABS 3.0A 20V~100V 0.55V~0.85V

Lead Devices

Part Number Package Io VRRM VF
1N5817~1N5819 DO-41 1.0A 20V~40V 0.45V~0.60V
1N5820~1N5822 DO-201AD 3.0A 20V~40V 0.475V~0.525V
SR120~SR1200 DO-41 1.0A 20V~200V 0.55V~0.85V
SK220~SK2200 DO-41 2.0A 20V~200V 0.55V~0.85V
SR220~SR2200 DO-15 2.0A 20V~200V 0.55V~0.85V
SK320~SK3200 DO-15 3.0A 20V~200V 0.55V~0.95V
SR320~SR3200 DO-201AD 3.0A 20V~200V 0.55V~0.95V
SR520~SR5200 DO-201AD 5.0A 20V~200V 0.55V~0.85V
SR620~SR6200 DO-201AD 6.0A 20V~200V 0.55V~0.90V
SR820~SR8100 DO-201AD 8.0A 20V~100V 0.65V~0.85V
MBR20200(F) TO-220AB/ITO220AB 20.0A 200V 0.72~0.92V
MBR2040~MBR2050 TO-220AB/ITO220AB 20.0A 40~50V 0.65~0.69V