ATE or Automated test equipment is used to test one or multiple devices at a time. This apparatus can conduct a single test or sequence of tests. You can use them for the testing of semiconductor devices, hardware and electronics. Pin electronics (PE) devices supply power and signals with precise currents and voltages. You can also use it to measure the electrical characteristics of the device under test. The following are the major blocks of pin electronics devices:
- Device power supply (DPS)
- Parametric measurement unit (PMU)
- ATE Comparator
The following are the supporting blocks:
- Analogue-to-digital converters (ADCs)
- Digital-to-analogue converters (DACs)
- Timing devices
The DCL drives signals to check DUT functionality over various levels of voltage and frequencies. This incorporates load conditions that can be configured. The tester’s DCL block tests a device’s AC characteristics. The following are the two critical parameters for automated test equipment products:
- Power consumption
- Tester speed
Pin electronics devices require low power consumption and operate at high speed with no compromise on signal fidelity.
It switches the device at different levels of voltage. Voltage levels are either set through analogue inputs or programmable. Integrated level-setting DACs and PE ICs support programming different levels of voltage through a serial interface. PE ICs without DACs set the levels of voltage through analogue inputs. The driver serves the purpose of a multiplexer switch between different levels of voltage. The driver also comes with additional features including adjustable output impedance, driver voltage clamps, slew-rate control and cable droop compensation.
Driver Cable Droop Compensation
Using lossy interconnects for operation degrades the output waveform. This results in unusable signals. Cable droop compensation circuitry compensates voltage droop.
Driver Voltage Clamps
Low voltage and high voltage clamps put a limitation on the voltage. They also suppress reflections. The analogue inputs/level-setting DACs can be used to set clamp voltages. The driver in high-impedance mode enables the clamps.
The high-speed comparator’s one input is connected to CLV or CHV and another is internally connected to DUT_ node. The input conditions’ logical results determine the ATE comparator’s output. There are two types of high-speed comparators including differential comparator and window comparator.
Testing is conducted under either unloaded or loaded conditions. Functional testing involves the load block. The load block also verifies the levels of current and voltage at different load conditions. Controlling serial interface bits enables and disables PE IC load. Active load and passive load are the two types of load in PE IC.
Parametric Measurement Unit (PMU)
PMU tests DUT’s DC characteristics. It forces voltages and currents into the DUT and then takes measurements. A test system architecture can either have a dedicated PMU for each pin or one PMU shared with multiple PE ICs.
Device Power Supply
It supplies the voltage for the device under test. The device power supply can be operated in force current mode (FI) and force voltage (FV) mode.
Clamps and Current Limit
Voltage control inputs of the DPS allow independent output voltage setting. DPS output comes with adjustable clamps to limit positive and negative currents and voltages.
A tester can be a memory tester or system-on-chip. System-on-chip tester allows to test each pin at different current/voltage levels. When it comes to memory testers, several drivers send data to DUT’s memory address.