What types of bias resistor built-in transistors (BRTs) are available?

In the basic form, a bias resistor built-in transistor (BRT) is composed of either an NPN or PNP transistor and two resistors (a series base resistor (R1) and a base-emitter resistor (R2)). These three devices are housed in one package. Single (1-in-1) and dual (2-in-1) BRTs are also available. Dual BRTs are available in common-emitter, point-symmetrical, and parallel configurations with different pinouts.
The following figure shows each type of NPN BRT.
Toshiba provides a wide range of BRTs, including PNP BRTs and dual BRTs containing NPN and PNP transistors in a point-symmetrical configuration.

Single

 

VESM

(SC-105AA,
SOT-723)
1.2×1.2

SSM

(SC-75,
SOT-416)
1.6×1.6

USM

(SC-70,
SOT-323)
2.0×2.1

S-Mini

(SC-59A, SOT-346,
TO-236MOD)
2.9×2.5

SOT23

(SC-105AA,
SOT-723)
2.9×2.4

Single
NPN  PNP NPN  PNP
NPN  PNP NPN  PNP NPN  PNP

Common emitter

 

ESV

(SC-107BB, SOT-553)
1.6×1.6

USV

(SC-88A, SOT-353)
2.0×2.1

SMV

(SC-74A, SOT-25)
2.9×2.8

Common emitter

NPN x2   PNP x2

NPN x2   PNP x2

NPN x2    PNP x2

Point symmetrical / Parallel

 

ES6
(SC-107C, SOT-563)
1.6×1.6

US6
(SC-88, SOT-363)
2.0×2.1

SM6
(SC-74, SOT-26)
2.9×2.8

Point symmetorical

NPN x2         PNP x2

NPN + PNP     PNP + NPN

NPN x2            PNP x2

NPN + PNP     PNP + NPN

NPN x2  PNP x2

               PNP + NPN

Parallel
  NPN x2  PNP x2  
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