February 16, 2017

National LM394CH - super matched BJT : weekend die-shot

National LM394CH - has 2x50 interleaved BJT transistors in parallel in order to get 2 transistors with well-matched parameters. This is often desired in discrete op-amps. Not sure why this trick is rarely used in integrated opamps.

Die size 1449x1347 µm.



Chip is soldered to ceramic substrate holder:
February 5, 2017

Espressif ESP32 - integrated Wi-Fi transceiver: weekend die-shot

Espressif ESP32 sets the new level for widely available WiFi/Bluetooth transceivers. Now with 2x LX108 CPU core and 520kB RAM. Surprisingly - includes integrated hall sensor. Manufactured on TSMC 40nm ULP technology. Huge upgrade over their previous highly successful ESP8266.

Hopefully next time we'll see their take on 5.8GHz ISM band.

Die size 2960x2850 µm (~double the area of ESP8266).



Closer look at RF part - some parts resemble ESP8266:


Thanks for the chips and modules to Espressif .
January 27, 2017

Analog Devices AD584 - precision voltage reference : weekend die-shot

Analog Devices AD584 is a voltage reference with 4 outputs : 2.5, 5, 7.5 and 10V. Tempco is laser trimmed to <15ppm/°C and voltage error to ~0.1%.


Die size 2236x1570 µm.

One can refer to a die photo from AD datasheet showing a bit older design of the same chip:

January 16, 2017

Vishay TSOP4838 - IR receiver module : weekend die-shot

Vishay TSOP4838 - decodes IR commands sent with 38kHz modulation. This modulation (and narrow-band filter on receiver module) is required to eliminate ambient light sources which could flicker somewhere at 50-100Hz or 20-30kHz (bad CFL/LEDs). Black (IR transparent) plastic also helps with background noise.


Die size 590x594 µm.

Photodiode is on a separate die:

Die size 1471x1471 µm
December 26, 2016

ST USBLC6-2 - USB protection chip : weekend die-shot

ST USBLC6-2 has 4 diodes and 1 Zener to protect your USB gear.
Die size 1084x547 µm.


December 18, 2016

LM338K - 5A linear regulator in TO-3 : weekend die-shot



Die size 1834x1609 µm.

You can see why this giant package is nearly obsolete these days (it's been around since 1955) - tiny crystal on a large steel case is largely limited by steel thermal conduction. Modern packages with copper base could do better with much smaller packages.


December 18, 2016

DTA143ZK - PNP BJT with bias resistors : weekend die-shot

Comparing to Infinion BCR185W there are no even bias resistors under the pads, hence larger die size (426x424 µm).