页 596 - 二极管 - 齐纳 - 单 | 分立半导体产品 | 深圳黑森尔电子
联系我们
SalesDept@heisener.com +86-0755-87210559 ext.802

二极管 - 齐纳 - 单

记录 73,474
页  596/2,450
图片
零件编号
制造商
描述
封装
库存
数量
Tolerance
Power - Max
Impedance (Max) (Zzt)
Current - Reverse Leakage @ Vr
Voltage - Forward (Vf) (Max) @ If
Operating Temperature
Mounting Type
Package / Case
Supplier Device Package
BZX84-C36/LF1R
NXP

DIODE ZENER TO-236AB SOT23

  • Voltage - Zener (Nom) (Vz): 36V
  • Tolerance: ±5%
  • Power - Max: 250mW
  • Impedance (Max) (Zzt): 90 Ohms
  • Current - Reverse Leakage @ Vr: 50nA @ 23.1V
  • Voltage - Forward (Vf) (Max) @ If: 900mV @ 10mA
  • Operating Temperature: -65°C ~ 150°C
  • Mounting Type: Surface Mount
  • Package / Case: TO-236-3, SC-59, SOT-23-3
  • Supplier Device Package: TO-236AB (SOT23)
封装: TO-236-3, SC-59, SOT-23-3
库存7,904
±5%
250mW
90 Ohms
50nA @ 23.1V
900mV @ 10mA
-65°C ~ 150°C
Surface Mount
TO-236-3, SC-59, SOT-23-3
TO-236AB (SOT23)
ZMM5242B-13
Vishay Semiconductor Diodes Division

DIODE ZENER SOD80 MINIMELF

  • Voltage - Zener (Nom) (Vz): 12V
  • Tolerance: ±5%
  • Power - Max: 500mW
  • Impedance (Max) (Zzt): 30 Ohms
  • Current - Reverse Leakage @ Vr: 1µA @ 9.1V
  • Voltage - Forward (Vf) (Max) @ If: 1.5V @ 200mA
  • Operating Temperature: -65°C ~ 175°C (TJ)
  • Mounting Type: Surface Mount
  • Package / Case: DO-213AC, MINI-MELF, SOD-80
  • Supplier Device Package: Mini MELF
封装: DO-213AC, MINI-MELF, SOD-80
库存5,392
±5%
500mW
30 Ohms
1µA @ 9.1V
1.5V @ 200mA
-65°C ~ 175°C (TJ)
Surface Mount
DO-213AC, MINI-MELF, SOD-80
Mini MELF
hot RLZTE-115.6B
Rohm Semiconductor

DIODE ZENER 5.6V 500MW LLDS

  • Voltage - Zener (Nom) (Vz): 5.6V
  • Tolerance: ±3%
  • Power - Max: 500mW
  • Impedance (Max) (Zzt): 13 Ohms
  • Current - Reverse Leakage @ Vr: 5µA @ 2.5V
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -
  • Mounting Type: Surface Mount
  • Package / Case: DO-213AC, MINI-MELF, SOD-80
  • Supplier Device Package: LLDS
封装: DO-213AC, MINI-MELF, SOD-80
库存9,742,956
±3%
500mW
13 Ohms
5µA @ 2.5V
-
-
Surface Mount
DO-213AC, MINI-MELF, SOD-80
LLDS
MMSZ4702ET3G
ON Semiconductor

DIODE ZENER 15V 500MW SOD123

  • Voltage - Zener (Nom) (Vz): 15V
  • Tolerance: ±5%
  • Power - Max: 500mW
  • Impedance (Max) (Zzt): -
  • Current - Reverse Leakage @ Vr: 50nA @ 11.4V
  • Voltage - Forward (Vf) (Max) @ If: 900mV @ 10mA
  • Operating Temperature: -55°C ~ 150°C
  • Mounting Type: Surface Mount
  • Package / Case: SOD-123
  • Supplier Device Package: SOD-123
封装: SOD-123
库存4,640
±5%
500mW
-
50nA @ 11.4V
900mV @ 10mA
-55°C ~ 150°C
Surface Mount
SOD-123
SOD-123
1N5236B_T50A
Fairchild/ON Semiconductor

DIODE ZENER 7.5V 500MW DO35

  • Voltage - Zener (Nom) (Vz): 7.5V
  • Tolerance: ±5%
  • Power - Max: 500mW
  • Impedance (Max) (Zzt): 6 Ohms
  • Current - Reverse Leakage @ Vr: 3µA @ 6V
  • Voltage - Forward (Vf) (Max) @ If: 1.2V @ 200mA
  • Operating Temperature: -65°C ~ 200°C
  • Mounting Type: Through Hole
  • Package / Case: DO-204AH, DO-35, Axial
  • Supplier Device Package: DO-35
封装: DO-204AH, DO-35, Axial
库存7,968
±5%
500mW
6 Ohms
3µA @ 6V
1.2V @ 200mA
-65°C ~ 200°C
Through Hole
DO-204AH, DO-35, Axial
DO-35
1PMT5944C/TR13
Microsemi Corporation

DIODE ZENER 62V 3W DO216AA

  • Voltage - Zener (Nom) (Vz): 62V
  • Tolerance: ±2%
  • Power - Max: 3W
  • Impedance (Max) (Zzt): 100 Ohms
  • Current - Reverse Leakage @ Vr: 1µA @ 47.1V
  • Voltage - Forward (Vf) (Max) @ If: 1.2V @ 200mA
  • Operating Temperature: -55°C ~ 150°C
  • Mounting Type: Surface Mount
  • Package / Case: DO-216AA
  • Supplier Device Package: DO-216AA
封装: DO-216AA
库存4,432
±2%
3W
100 Ohms
1µA @ 47.1V
1.2V @ 200mA
-55°C ~ 150°C
Surface Mount
DO-216AA
DO-216AA
BZD27C75PWHRVG
Taiwan Semiconductor Corporation

DIODE, ZENER, 75V, 1000MW, %, AE

  • Voltage - Zener (Nom) (Vz): 75V
  • Tolerance: ±5%
  • Power - Max: 1W
  • Impedance (Max) (Zzt): 100 Ohms
  • Current - Reverse Leakage @ Vr: 1µA @ 56V
  • Voltage - Forward (Vf) (Max) @ If: 1V @ 200mA
  • Operating Temperature: -55°C ~ 175°C (TJ)
  • Mounting Type: Surface Mount
  • Package / Case: SOD-123W
  • Supplier Device Package: SOD123W
封装: SOD-123W
库存7,120
±5%
1W
100 Ohms
1µA @ 56V
1V @ 200mA
-55°C ~ 175°C (TJ)
Surface Mount
SOD-123W
SOD123W
CZRUR52C9V1
Comchip Technology

DIODE ZENER 9.1V 150MW 0603

  • Voltage - Zener (Nom) (Vz): 9.1V
  • Tolerance: ±5%
  • Power - Max: 150mW
  • Impedance (Max) (Zzt): 10 Ohms
  • Current - Reverse Leakage @ Vr: 100nA @ 7V
  • Voltage - Forward (Vf) (Max) @ If: 900mV @ 10mA
  • Operating Temperature: -55°C ~ 125°C
  • Mounting Type: Surface Mount
  • Package / Case: 2-SMD, No Lead
  • Supplier Device Package: 0603/SOD-523F
封装: 2-SMD, No Lead
库存5,856
±5%
150mW
10 Ohms
100nA @ 7V
900mV @ 10mA
-55°C ~ 125°C
Surface Mount
2-SMD, No Lead
0603/SOD-523F
hot BZD27C3V9P-E3-08
Vishay Semiconductor Diodes Division

DIODE ZENER 800MW SMF DO219

  • Voltage - Zener (Nom) (Vz): 3.9V
  • Tolerance: -
  • Power - Max: 800mW
  • Impedance (Max) (Zzt): 8 Ohms
  • Current - Reverse Leakage @ Vr: 50µA @ 1V
  • Voltage - Forward (Vf) (Max) @ If: 1.2V @ 200mA
  • Operating Temperature: -65°C ~ 175°C
  • Mounting Type: Surface Mount
  • Package / Case: DO-219AB
  • Supplier Device Package: DO-219AB (SMF)
封装: DO-219AB
库存288,000
-
800mW
8 Ohms
50µA @ 1V
1.2V @ 200mA
-65°C ~ 175°C
Surface Mount
DO-219AB
DO-219AB (SMF)
JANTX1N6319
Microsemi Corporation

DIODE ZENER 6.2V 500MW DO35

  • Voltage - Zener (Nom) (Vz): 6.2V
  • Tolerance: ±5%
  • Power - Max: 500mW
  • Impedance (Max) (Zzt): 3 Ohms
  • Current - Reverse Leakage @ Vr: 5µA @ 3.5V
  • Voltage - Forward (Vf) (Max) @ If: 1.4V @ 1A
  • Operating Temperature: -65°C ~ 175°C
  • Mounting Type: Through Hole
  • Package / Case: DO-204AH, DO-35, Axial
  • Supplier Device Package: DO-35
封装: DO-204AH, DO-35, Axial
库存5,376
±5%
500mW
3 Ohms
5µA @ 3.5V
1.4V @ 1A
-65°C ~ 175°C
Through Hole
DO-204AH, DO-35, Axial
DO-35
hot BZT52C15S-TP
Micro Commercial Co

DIODE ZENER 15V 200MW SOD323

  • Voltage - Zener (Nom) (Vz): 15V
  • Tolerance: ±6%
  • Power - Max: 200mW
  • Impedance (Max) (Zzt): 30 Ohms
  • Current - Reverse Leakage @ Vr: 100nA @ 10.5V
  • Voltage - Forward (Vf) (Max) @ If: 900mV @ 10mA
  • Operating Temperature: -65°C ~ 150°C
  • Mounting Type: Surface Mount
  • Package / Case: SC-76, SOD-323
  • Supplier Device Package: SOD-323
封装: SC-76, SOD-323
库存22,800
±6%
200mW
30 Ohms
100nA @ 10.5V
900mV @ 10mA
-65°C ~ 150°C
Surface Mount
SC-76, SOD-323
SOD-323
JANTXV1N4101-1
Aeroflex Metelics, Division of MACOM

DIODE ZENER 8.2V 500MW DO35

  • Voltage - Zener (Nom) (Vz): 8.2V
  • Tolerance: ±5%
  • Power - Max: 500mW
  • Impedance (Max) (Zzt): 200 Ohms
  • Current - Reverse Leakage @ Vr: 1µA @ 6.24V
  • Voltage - Forward (Vf) (Max) @ If: 1.1V @ 200mA
  • Operating Temperature: -65°C ~ 175°C
  • Mounting Type: Through Hole
  • Package / Case: DO-204AH, DO-35, Axial
  • Supplier Device Package: DO-35
封装: DO-204AH, DO-35, Axial
库存7,840
±5%
500mW
200 Ohms
1µA @ 6.24V
1.1V @ 200mA
-65°C ~ 175°C
Through Hole
DO-204AH, DO-35, Axial
DO-35
hot BZT52C3V6S-7-F
Diodes Incorporated

DIODE ZENER 3.6V 200MW SOD323

  • Voltage - Zener (Nom) (Vz): 3.6V
  • Tolerance: ±6%
  • Power - Max: 200mW
  • Impedance (Max) (Zzt): 90 Ohms
  • Current - Reverse Leakage @ Vr: 5µA @ 1V
  • Voltage - Forward (Vf) (Max) @ If: 900mV @ 10mA
  • Operating Temperature: -65°C ~ 150°C
  • Mounting Type: Surface Mount
  • Package / Case: SC-76, SOD-323
  • Supplier Device Package: SOD-323
封装: SC-76, SOD-323
库存33,600
±6%
200mW
90 Ohms
5µA @ 1V
900mV @ 10mA
-65°C ~ 150°C
Surface Mount
SC-76, SOD-323
SOD-323
MMSZ5236BS_R1_00001
Panjit International Inc.

SURFACE MOUNT SILICON ZENER DIOD

  • Voltage - Zener (Nom) (Vz): 7.5 V
  • Tolerance: ±5%
  • Power - Max: 200 mW
  • Impedance (Max) (Zzt): 6 Ohms
  • Current - Reverse Leakage @ Vr: 3 µA @ 6 V
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -55°C ~ 150°C (TJ)
  • Mounting Type: Surface Mount
  • Package / Case: SC-90, SOD-323F
  • Supplier Device Package: SOD-323
封装: -
库存15,000
±5%
200 mW
6 Ohms
3 µA @ 6 V
-
-55°C ~ 150°C (TJ)
Surface Mount
SC-90, SOD-323F
SOD-323
JANKCA1N4109D
Microchip Technology

VOLTAGE REGULATOR

  • Voltage - Zener (Nom) (Vz): 15 V
  • Tolerance: ±1%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): 100 Ohms
  • Current - Reverse Leakage @ Vr: 50 nA @ 11.4 V
  • Voltage - Forward (Vf) (Max) @ If: 1.1 V @ 200 mA
  • Operating Temperature: -65°C ~ 175°C
  • Mounting Type: Surface Mount
  • Package / Case: Die
  • Supplier Device Package: Die
封装: -
Request a Quote
±1%
500 mW
100 Ohms
50 nA @ 11.4 V
1.1 V @ 200 mA
-65°C ~ 175°C
Surface Mount
Die
Die
MTZJ12SA
Taiwan Semiconductor Corporation

DO-34, 500MW, 2%, SMALL SIGNAL Z

  • Voltage - Zener (Nom) (Vz): 11.42 V
  • Tolerance: ±2%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): 30 Ohms
  • Current - Reverse Leakage @ Vr: 200 nA @ 9 V
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -55°C ~ 175°C (TJ)
  • Mounting Type: Through Hole
  • Package / Case: DO-204AG, DO-34, Axial
  • Supplier Device Package: DO-34
封装: -
Request a Quote
±2%
500 mW
30 Ohms
200 nA @ 9 V
-
-55°C ~ 175°C (TJ)
Through Hole
DO-204AG, DO-34, Axial
DO-34
JANTXV1N6346CUS-TR
Microchip Technology

VOLTAGE REGULATOR

  • Voltage - Zener (Nom) (Vz): 82 V
  • Tolerance: ±2%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): 220 Ohms
  • Current - Reverse Leakage @ Vr: 50 nA @ 62 V
  • Voltage - Forward (Vf) (Max) @ If: 1.4 V @ 1 A
  • Operating Temperature: -65°C ~ 175°C (TJ)
  • Mounting Type: Surface Mount
  • Package / Case: SQ-MELF, B
  • Supplier Device Package: B, SQ-MELF
封装: -
Request a Quote
±2%
500 mW
220 Ohms
50 nA @ 62 V
1.4 V @ 1 A
-65°C ~ 175°C (TJ)
Surface Mount
SQ-MELF, B
B, SQ-MELF
RD4-3ES-T4-AZ
Renesas Electronics Corporation

DIODE ZENER

  • Voltage - Zener (Nom) (Vz): -
  • Tolerance: -
  • Power - Max: -
  • Impedance (Max) (Zzt): -
  • Current - Reverse Leakage @ Vr: -
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -
  • Mounting Type: -
  • Package / Case: -
  • Supplier Device Package: -
封装: -
Request a Quote
-
-
-
-
-
-
-
-
-
CD4680
Microchip Technology

VOLTAGE REGULATOR

  • Voltage - Zener (Nom) (Vz): 2.2 V
  • Tolerance: ±5%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): -
  • Current - Reverse Leakage @ Vr: 4 µA @ 1 V
  • Voltage - Forward (Vf) (Max) @ If: 1.5 V @ 200 mA
  • Operating Temperature: -65°C ~ 175°C
  • Mounting Type: Surface Mount
  • Package / Case: Die
  • Supplier Device Package: Die
封装: -
Request a Quote
±5%
500 mW
-
4 µA @ 1 V
1.5 V @ 200 mA
-65°C ~ 175°C
Surface Mount
Die
Die
1N5939DG
Microsemi Corporation

DIODE ZENER 39V 1.25W DO204AL

  • Voltage - Zener (Nom) (Vz): 39 V
  • Tolerance: ±1%
  • Power - Max: 1.25 W
  • Impedance (Max) (Zzt): 45 Ohms
  • Current - Reverse Leakage @ Vr: 1 µA @ 29.7 V
  • Voltage - Forward (Vf) (Max) @ If: 1.2 V @ 200 mA
  • Operating Temperature: -65°C ~ 175°C
  • Mounting Type: Through Hole
  • Package / Case: DO-204AL, DO-41, Axial
  • Supplier Device Package: DO-204AL (DO-41)
封装: -
Request a Quote
±1%
1.25 W
45 Ohms
1 µA @ 29.7 V
1.2 V @ 200 mA
-65°C ~ 175°C
Through Hole
DO-204AL, DO-41, Axial
DO-204AL (DO-41)
BZX84B3V6W_R1_00001
Panjit International Inc.

SURFACE MOUNT SILICON ZENER DIOD

  • Voltage - Zener (Nom) (Vz): 3.6 V
  • Tolerance: ±2.08%
  • Power - Max: 200 mW
  • Impedance (Max) (Zzt): 90 Ohms
  • Current - Reverse Leakage @ Vr: 5 µA @ 1 V
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -55°C ~ 150°C (TJ)
  • Mounting Type: Surface Mount
  • Package / Case: SC-70, SOT-323
  • Supplier Device Package: SOT-323
封装: -
Request a Quote
±2.08%
200 mW
90 Ohms
5 µA @ 1 V
-
-55°C ~ 150°C (TJ)
Surface Mount
SC-70, SOT-323
SOT-323
JANS1N4464US
Microchip Technology

ZENER DIODE

  • Voltage - Zener (Nom) (Vz): 9.1 V
  • Tolerance: ±5%
  • Power - Max: 1.5 W
  • Impedance (Max) (Zzt): 4 Ohms
  • Current - Reverse Leakage @ Vr: 300 nA @ 5.46 V
  • Voltage - Forward (Vf) (Max) @ If: 1.5 V @ 1 A
  • Operating Temperature: -65°C ~ 175°C (TJ)
  • Mounting Type: Surface Mount
  • Package / Case: SQ-MELF, A
  • Supplier Device Package: A, SQ-MELF
封装: -
Request a Quote
±5%
1.5 W
4 Ohms
300 nA @ 5.46 V
1.5 V @ 1 A
-65°C ~ 175°C (TJ)
Surface Mount
SQ-MELF, A
A, SQ-MELF
MMSZ4699T1
onsemi

DIODE ZENER 12V 500MW SOD-123

  • Voltage - Zener (Nom) (Vz): 12 V
  • Tolerance: ±5%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): -
  • Current - Reverse Leakage @ Vr: 50 nA @ 9.1 V
  • Voltage - Forward (Vf) (Max) @ If: 900 mV @ 10 mA
  • Operating Temperature: -55°C ~ 150°C
  • Mounting Type: Surface Mount
  • Package / Case: SOD-123
  • Supplier Device Package: SOD-123
封装: -
Request a Quote
±5%
500 mW
-
50 nA @ 9.1 V
900 mV @ 10 mA
-55°C ~ 150°C
Surface Mount
SOD-123
SOD-123
1N968B-TR-PBFREE
Central Semiconductor Corp

DIODE ZENER 20V 500MW DO35

  • Voltage - Zener (Nom) (Vz): 20 V
  • Tolerance: ±5%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): 25 Ohms
  • Current - Reverse Leakage @ Vr: 5 µA @ 15.2 V
  • Voltage - Forward (Vf) (Max) @ If: 1.5 V @ 200 mA
  • Operating Temperature: -65°C ~ 200°C (TJ)
  • Mounting Type: Through Hole
  • Package / Case: DO-204AH, DO-35, Axial
  • Supplier Device Package: DO-35
封装: -
Request a Quote
±5%
500 mW
25 Ohms
5 µA @ 15.2 V
1.5 V @ 200 mA
-65°C ~ 200°C (TJ)
Through Hole
DO-204AH, DO-35, Axial
DO-35
JAN1N6339D
Microchip Technology

VOLTAGE REGULATOR

  • Voltage - Zener (Nom) (Vz): 43 V
  • Tolerance: ±1%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): 65 Ohms
  • Current - Reverse Leakage @ Vr: 50 nA @ 33 V
  • Voltage - Forward (Vf) (Max) @ If: 1.4 V @ 1 A
  • Operating Temperature: -65°C ~ 175°C (TJ)
  • Mounting Type: Through Hole
  • Package / Case: DO-204AH, DO-35, Axial
  • Supplier Device Package: DO-204AH (DO-35)
封装: -
Request a Quote
±1%
500 mW
65 Ohms
50 nA @ 33 V
1.4 V @ 1 A
-65°C ~ 175°C (TJ)
Through Hole
DO-204AH, DO-35, Axial
DO-204AH (DO-35)
RKZ10BJKU-P6
Renesas Electronics Corporation

DIODE ZENER 10V

  • Voltage - Zener (Nom) (Vz): -
  • Tolerance: -
  • Power - Max: -
  • Impedance (Max) (Zzt): -
  • Current - Reverse Leakage @ Vr: -
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -
  • Mounting Type: -
  • Package / Case: -
  • Supplier Device Package: -
封装: -
Request a Quote
-
-
-
-
-
-
-
-
-
1N6027UR-1
Microchip Technology

DIODE ZENER

  • Voltage - Zener (Nom) (Vz): -
  • Tolerance: -
  • Power - Max: -
  • Impedance (Max) (Zzt): -
  • Current - Reverse Leakage @ Vr: -
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -
  • Mounting Type: -
  • Package / Case: -
  • Supplier Device Package: -
封装: -
Request a Quote
-
-
-
-
-
-
-
-
-
RD9-1ES-T4-AZ
Renesas Electronics Corporation

DIODE ZENER

  • Voltage - Zener (Nom) (Vz): -
  • Tolerance: -
  • Power - Max: -
  • Impedance (Max) (Zzt): -
  • Current - Reverse Leakage @ Vr: -
  • Voltage - Forward (Vf) (Max) @ If: -
  • Operating Temperature: -
  • Mounting Type: -
  • Package / Case: -
  • Supplier Device Package: -
封装: -
Request a Quote
-
-
-
-
-
-
-
-
-
BZT52-B5V6X
Nexperia USA Inc.

DIODE ZENER 5.6V 590MW SOD123

  • Voltage - Zener (Nom) (Vz): 5.6 V
  • Tolerance: ±1.96%
  • Power - Max: 590 mW
  • Impedance (Max) (Zzt): 40 Ohms
  • Current - Reverse Leakage @ Vr: 1 µA @ 2 V
  • Voltage - Forward (Vf) (Max) @ If: 900 mV @ 10 mA
  • Operating Temperature: -55°C ~ 150°C (TA)
  • Mounting Type: Surface Mount
  • Package / Case: SOD-123
  • Supplier Device Package: SOD-123
封装: -
库存11,508
±1.96%
590 mW
40 Ohms
1 µA @ 2 V
900 mV @ 10 mA
-55°C ~ 150°C (TA)
Surface Mount
SOD-123
SOD-123
MM5Z8V2T5G
onsemi

DIODE ZENER 8.2V 500MW SOD523

  • Voltage - Zener (Nom) (Vz): 8.2 V
  • Tolerance: ±6.1%
  • Power - Max: 500 mW
  • Impedance (Max) (Zzt): 15 Ohms
  • Current - Reverse Leakage @ Vr: 700 nA @ 5 V
  • Voltage - Forward (Vf) (Max) @ If: 900 mV @ 10 mA
  • Operating Temperature: -65°C ~ 150°C (TJ)
  • Mounting Type: Surface Mount
  • Package / Case: SC-79, SOD-523
  • Supplier Device Package: SOD-523
封装: -
Request a Quote
±6.1%
500 mW
15 Ohms
700 nA @ 5 V
900 mV @ 10 mA
-65°C ~ 150°C (TJ)
Surface Mount
SC-79, SOD-523
SOD-523