+
±
V
+
±
A
+
±
A
DC
Power
Supply
Voltmeter
+
s
Function
Generator
Ammeter
Ammeter
Connector Description
3
Connector Description
This section describes the connectors and test points on the EVM and how to properly connect, setup,
and use the TPS92691EVM-001.
Figure 1. Connection Diagram
3.1
J1, VIN, GND
The screw-down connector, J1, marked VIN and GND is for connecting the EVM to the DC input voltage
supply. One other VIN and PGND test point is provided on the board that can also be used for all
purposes but input power.
3.2
J2, LED+, LED–
The screw-down connector, J2, marked LED+ and LED– is for connecting the LED load to the board. The
leads to the LED load should be twisted and kept as short as possible to minimize voltage drop,
inductance, and EMI transmission. This design is for approximately 1 to
≈
20 white LEDs.
3.3
TP1, SHUTDOWN
The test point SHUTDOWN connects through a 1-k
Ω
resistor to the SS pin of the TPS92691-Q1 device.
The voltage range is from 0 V to 5 V, if driven externally. The SS voltage can be monitored with this test
point. Pulling SHUTDOWN to GND will also serve to disable the part and put it into STANDBY mode.
3.4
TP2, SYNC
The SYNC test point is AC-coupled to the RT/SYNC pin of the TPS92691-Q1 device through a 100-pF
capacitor. Apply a square wave with pulse width greater than 200 ns and logic-low level of GND and a
high level between 3 V and 5 V to synchronize the switching frequency to the applied frequency. The
frequency range of SYNC is from 332 kHz to 449 kHz (±15%) for the nominal set point of 390-kHz
switching frequency.
3.5
TP3, PWM
The PWM test point connects through a 1-k
Ω
resistor to the PWM pin of the TPS92691-Q1 device. Leave
open for normal operation. If PWM dimming is used, apply a square wave with a low level of GND and a
high level of between 3 V and 5 V. The dimming frequency range is 100 Hz to 1 kHz.
4
TPS92691 SEPIC LED Driver Evaluation Board
SLVUAL8 – December 2015
Copyright © 2015, Texas Instruments Incorporated