ALLEGRO APM80950 Evaluation Board User Manual

Contents hide

1 ALLEGRO APM80950 Evaluation Board

2 GENERAL SPECIFICATIONS

3 OPERATING INSTRUCTIONS

4 EMI PERFORMANCE

5 DEMO PCB LAYOUT

6 Documents / Resources

6.1 References

7 Related Posts

ALLEGRO APM80950 Evaluation Board

EMC filter configuration

Schematic for APM80950

GENERAL SPECIFICATIONS

GENERAL SPECIFICATIONS
Specification	Min	Nom.	Max.	Units
Absolute Maximum Input Voltage	–0.3	−	40	V
Operating Input Voltage Range	4.5	−	36	V
VVIN START Threshold, VVIN rising	−	−	4.3	V
VVIN UVLO Hysteresis	100	−	300	mV
LED Regulation Current	−	−	1.5	A
Enable Input	–0.3	−	VVIN + 0.3	V
VCC, ADIM, RNG, FDSET, FFn, PWM Terminal Voltages	–0.3	−	7	V

BILL OF MATERIALS

Designator	Description	Footprint	Quantity	Manufacturer	Manufacturer P/N	Source	Purchase P/N
PCB	TED-0003126-PCB (APM80900/04/50/51 PCB)	N/A	1	Allegro MicroSystems
U1	APM80950 IC	QFN-32	1	Allegro MicroSystems	APM80950KNBATR
RS1	Resistor, 0.2 Ω, 1/2 W, 1%	1206	1	Susumu	RL1632R-R200-F	Digikey	RL16R.20FCT-ND
Rfdt	Resistor, 100 kΩ, 1/16 W, 1%	0402	1	Panasonic Electronic	ERA-2AED104X	Digikey	P100KDECT-ND
Rfdb	Resistor, 300 kΩ, 1/16 W, 1%	0402	1	Panasonic Electronic	ERJ-2RKF3003X	Digikey	P300KLCT-ND
REN, Rffn	Resistor, 10 kΩ, 1/16 W, 1%	0402	2	Panasonic Electronic	ERA-2AED103X	Digikey	P10KDECT-ND
Rdrb, RngH, RFPWM	Resistor, 0 kΩ, JUMPER 1/16 W	0402	3	Vishay Dale	CRCW04020000Z0ED	Digikey	541-0.0JCT-ND
Rdrt, RngL	Empty	0402	0
CV	Capacitor, Ceramic, 1.0 µF, 50 V,10%, X7R	0603	1	Taiyo Yuden	UMK107AB7105KA-T	Digikey	587-3247-1-ND
CL1	Capacitor, Ceramic, 0.047 µF, 100 V, X7R 0805	0805	1	Murata TDK	GCM21BR72A473KA37L C2012X7R2A473K125AA	Digikey	490-4969-1-ND 445-2276-1-ND
Cin1, Cin3, CF3, Ccs	Empty	Various	0
Cin2	Capacitor, Ceramic, 4.7 µF, 50 V, X7S	0805	1	Murata	GRM21BC71H475KE11L	Digikey	490-12757-1-ND
FB1	0805 SMT FERRITE BEAD, 120 Ω @ 100 MHz, 3 A	0805	1	Wurth Electronics	742792023	Digikey	732-1613-1-ND
D1	DIODE SCHOTTKY 100 V 2 A DO220AA	DO-220AA (SMP)	1	Vishay	SS2PH10HM3/84A	Digikey	SS2PH10HM3/ 84AGITR-ND
Lf	FIXED IND 6.8 µH 3 A 74 MΩ SMD	4.1 × 4.1 mm 3.1 mm thick	1	Wurth Electronics	74438357068	Digikey	732-11204-1-ND
CF1	Capacitor, Ceramic, 10 nF, 100 V, 10%, X7R	0603	1	TDK	C1608X7R2A103K080AA	Digikey	445-1304-1-ND
CF2	Capacitor, Ceramic, 0.47 µF, 100 V, X7R	1210	1	TDK	CGA6M3X8R2A474K200AB	Digikey	445-13052-1-ND
Cinf	Capacitor, Ceramic, 4.7 µF, 100 V, X7R	1210	1	TDK	CGA6M3X7S2A475K200AB	Digikey	445-7005-1-ND
VIN, LED+	Test Points, Red, 0.063″ diameter	0.063″	2	Keystone	5010	Digikey	5010K-ND
EN, PWM, ADIM, FFn, VCC	Test Points, White, 0.063″ diameter	0.063″	5	Keystone	5012	Digikey	5012K-ND
GND	Test Points, Black, 0.063″ diameter	0.063″	4	Keystone	5011	Digikey	5011K-ND
P1	Header, Male, 2 position (open)	0.1″ pitch	1	Sullins	PEC02SAAN	Digikey	S1012E-02-ND
PL1, PL2	CONN TERM BLOCK 2 POS 5.08 MM PCB		2	Phoenix Contact	1715721	Digikey	277-1263-ND
Rubber Feet	Self stick rubber feet	Clear	4	3M	SJ-5303 (CLEAR)	Digikey	SJ5303-7-ND

CONFIGURATIONS (Refer to Datasheet)

The customer APM80950 EVB is configured for external PWM dimming operation mode only, so an external PWM dimming signal at test point PWM must be applied because the PWM pin is pulled down to GND through an internal resistor. Put jumper on P1 connector to connect EN to VIN through a resistor to enable the unit. RngH or RngL resistors determine the LED current range high or low:

RNG = VCC by making RngH = 0 Ω and RngL = Open	Full rated voltage VCSREG across current sensing resistor Rs1 = 200 mV	iLED = 0.2 / Rs1
RNG = GND by making RngH = Open and RngL = 0 Ω	Full rated voltage VCSREG across current sensing resistor Rs1 = 100 mV	iLED = 0.1 / Rs1

The regulation LED current level is determined by the current sensing resistor on board: iLED = 0.2 / Rsense (A) On EVB, there is one current sensing resistor, Rs1 = 0.2 Ω. Because RNG = VCC, the full LED current is 1 A.
Apply external analog dimming signal at test point ADIM. Do not leave ADIM floating. ADIM pin voltage controls the LED current reference voltage across Rs1 according to the equation below VCSREG = (VADIM – 0.4) / 5 (V) The calculation and actual test results are shown below as reference to select the desired ADIM voltage.

OPERATING INSTRUCTIONS

Refer to figure below for demo board setup. In order to enable the EVB, use the attached jumper to short the connector P1 so that EN is connected to VIN, or apply a voltage level above 1.8 V to the test point EN if the jumper is not used. Apply the desired ADIM voltage at ADIM test point. Apply PWM signal at PWM test point. Connect LED load between LED+ to GND; apply input power supply.