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Texas Instruments Little Professor (1978)

Date of introduction:	December 1978	Display technology:	LED-stick
New price:		Display size:	8
Size:	5.0" x 3.5" x 1.1" 127 x 89 x 29 mm³
Weight:	3.8 ounces, 107 grams	Serial No:
Batteries:	9V	Date of manufacture:	wk 36 year 1979
AC-Adapter:		Origin of manufacture:	USA (ATA)
Precision:		Integrated circuits:	TMC1993
Memories:
Program steps:		Courtesy of:	Joerg Woerner

You know this cute math trainer, the Little Professor. Millions and millions were sold in the past 5 decades from this simple but funny educational product. The basic idea behind the Little Professor is opposite to a normal calculator: The child has to type the answer of simple questions like "3 + 5 = ?". You can choose between the four basic math functions and four different grade levels. If the child gives a wrong answer "EEE" occurs, otherwise another of more than 16000 different questions is asked.

From the technology this Little Professor from 1978 is similar to the TI-1000 calculator of the same epoch. This second version of the Little Professor could easily recognized at the [ON], [OFF] keys and the [LEVEL] key to adjust the grade level. Compare it with the Little Professor (1976).

Dismantling multiple Little Professor (1978) devices reveals a surprise - some models use inside a flexible printed circuit board (Flex-PCB) and some a Rigid-PCB. While the first version of the TI-1000 used a TMC1991 packaged in 28-pin SPDIP (Shrink Plastic Dual In-line Package) with Die-up (standard pinout) on a two-sided Rigid-PCB and the second version a TMC1992 packaged in 28-pin SPDIP (Shrink Plastic Dual In-line Package) with Die-down (reverse pinout) on a single-sided Flex-PCB, reversed the Little Professor (1978) the sequence:

• Little Professor (1978-1979): TMC1993 packaged in 28-pin SPDIP (Shrink Plastic Dual In-line Package) with Die-down (reverse pinout) on a single-sided Flex-PCB
• Little Professor (1979-1980): TMC1993 packaged in 28-pin SPDIP (Shrink Plastic Dual In-line Package) with Die-up (standard pinout) on a two-sided Rigid-PCB

Consequently the Little Professor (1978) from a later production (January 1980) with Rigid-PCB uses an "unmarked" TMC1993 while a Little Professor (1980) manufactured in September 1980 sports a chip marked TMC1993.

The 5^th row of the keyboard with the keys [OFF], [SET] and [LEVEL] breaks the design of the Little Professor. Already in 1980 a new, smaller keyboard was available and this one matched the original design. The picture on the right combines this Little Professor (1978) with the later Little Professor (1980).

Don't miss a Little Professor Solar acquired in June 2026 from Texas Instruments to celebrate the 50^th Anniversary of the original Little Professor.

If you have additions to the above article please email: joerg@datamath.org.