View GR8876_7829296.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 1 GR8876 features high-voltage (500v) startup circuit current mode pwm very low startup current (<20ua) under-voltage lockout (uvlo) non-audible-noise green-mode control programmable switching frequency cycle-by-cycle peak current limiting internal leading-edge blanking internal slope compensation internal 4ms soft start (fs = 65khz) vcc over-voltage clamp gate output voltage clamp soft driving for reducing emi over-voltage protection (ovp) on vcc pin over-load protection (olp) over-current protection (ocp) on cs pin 500ma driving capability applications open-frame smps switching ac/dc adapter and battery charger description the GR8876 is a highly-integrated, low startup current, current mode pwm controller with green-mode function and high-voltage start up circuit. a high-voltage current source supplies th e start up current and the traditional start up resistance can be saved in order to limit the power cost. the controller also includes the leading-edg e blanking of the current sensing, internal slope compensation and cycle-by-cycle peak current limiting. it is also integrated soft driving for reducing emi, gate output voltage clamp function fo r protecting power mosfet. GR8876 provides several protections such as olp, ovp, and ocp for fault conditions. the GR8876 improves the performance and reduces the cost of power supplies. it is available in both 8-pin sop and 8-p in dip package. ordering and marking information dip-8 xxxxx ? date code sop-8 xxxxx ? date code grenergy opto inc. reserves the right to make change s to improve reliability or manufacture ability wit hout notice, and advise customers to obtain the latest version of re levant information to verify before placing orders. green-mode pwm controller with integrated protectio ns gr88 76 x xxxx gr88 76 x xxxx
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 2 GR8876 pin configuration top view pin description pin symbol description 1 rt connecting a resistor to ground, this resistor determine the switching frequency 2 comp voltage feedback pin, by connecting a photo- coupler to control the duty cycle 3 cs current sense pin, connect to sense the mosfet current 4 gnd ground 5 out the output for driving the external mosfet 6 vcc power supply pin 7 nc unconnected pin 8 hv this pin is connected to positive terminal of bulk capacitor. it provides the startup current. when uvlo (on) is tripped, this hv loop wi ll be off thus limit the power loss on the startup circuit. absolute maximum ratings supply voltage vcc ------------------------------- --------------------------------------------------- ----------------------- 35v high-voltage pin, hv ----------------------------- --------------------------------------------------- -------------- - 0.3 ~ 500v comp, rt, cs ------------------------------------- --------------------------------------------------- ----------------- -0.3 ~ 7v junction temperature ----------------------------- --------------------------------------------------- --------------------- 150 operating ambient temperature -------------------- --------------------------------------------------- ------- - 20 ~ 85 storage temperature range ------------------------ --------------------------------------------------- ------- - 65 ~ 150 sop-8 package thermal resistance ----------------- --------------------------------------------------- ----------- 160 /w dip-8 package thermal resistance ----------------- --------------------------------------------------- ---------- 100 /w power dissipation (sop-8, at ambient temperature = 85 ) ------------------------------------------------ 400 mw power dissipation (dip-8, at ambient temperature = 85 ) ------------------------------------------------- -- 650mw lead temperature (sop-8 & dip-8, soldering, 10sec) ------------------------------------------------- ------- 230 lead temperature (all pb free packages, soldering, 10sec) ------------------------------------------- ----- 260 esd voltage protection, human body model (except hv pin) -------------------------------------------- ---- 3kv esd voltage protection, machine model ------------ --------------------------------------------------- ------------- 250v
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 3 GR8876 recommended operating conditions item min. max. unit supply voltage vcc 11 25 v switching frequency 50 130 khz block diagram
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 4 GR8876 electrical characteristics (t a = +25 unless otherwise stated, v cc = 15.0v) parameter pin min. typ. max. unit high-voltage supply (hv pin) high-voltage current source (vcc = 0v) 8 0.5 1.0 1.55 ma off-state leakage current 8 0 25 ua supply voltage startup current 6 20 ua operating current (with 1nf load on out pin), vcomp = 0v 6 1 2.3 3.3 ma operating current (with 1nf load on out pin), vcomp = 2.5v 6 1.5 2.5 4.0 ma operating current (with 1nf load on out pin), prote ction tripped (olp, ovp) 6 0.1 0.5 1 ma uvlo (on) 6 13.5 14.5 15.8 v uvlo (off) 6 8.0 9.0 10.0 v ovp level on vcc pin 6 26.5 27.5 30 v vcc zener clamp 6 35 v voltage feedback short circuit current, vcomp = 0v 2 1 1.5 2 ma open loop voltage, comp pin open 2 5 5.6 6 v green mode threshold voltage 2 1.2 v current sensing maximum input voltage, vcs (off) 3 0.80 0.85 0.90 v leading-edge blanking time 3 250 350 550 ns input impedance 3 1 m delay to output 3 100 ns oscillator frequency (rt = 100k ) 3 60 65 70 khz green mode frequency (rt = 100k ) 3 18 22 28 khz temp. stability (- 40c ~ 110c) 3 3 % voltage stability (vcc = 11v ~ 25v) 3 3 % gate driver output output low level, vcc = 15v, io = 20ma 1 1 v output high level, vcc = 15v, io = 20ma 1 8 v rising time, load capacitance = 1000pf 1 150 ns falling time, load capacitance = 1000pf 1 50 ns olp olp trip level, vcomp (olp) - 3.3 3.6 4 v olp delay time (note), fs = 65khz - 60 ms
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 5 GR8876 typical performance characteristics 0.6 0.8 1 1.2 1.4 1.6 1.8 -40 0 40 80 120 t/ h v c u r r e n t / m a fig.1 13 13.8 14.6 15.4 16.2 17 -40 0 40 80 120 t/ u v l o o n / v fig.3 60 62 64 66 68 70 -40 0 40 80 120 t/ f o s c / k h z fig.5 0.8 0.81 0.82 0.83 0.84 0.85 -40 0 40 80 120 t/ v c s o f f / v fig.2 7 7.8 8.6 9.4 10.2 11 -40 0 40 80 120 t/ u v l o o f f / v fig.4 15 17 19 21 23 25 -40 0 40 80 120 t/ f g / k h z fig.6
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 6 GR8876 typical performance characteristics (cont.) fig.7 fig.9 4 4.5 5 5.5 6 6.5 -40 0 40 80 120 t/ v c o m p o p e n / v fig.11 60 65 70 75 80 85 -40 0 40 80 120 t/ m a x d u t y / fig.8 fig.10 3.5 3.6 3.7 3.8 3.9 -40 0 40 80 120 t/ o l p / v fig. 12
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 7 GR8876 application information overview the GR8876 integrates several functions that are needed in the market. it includes green-mode controller and high-voltage start-up circuit which can save the power loss after startup. high-voltage startup circuit and under-voltage lockout (uvlo) GR8876 implements a high-voltage startup circuit, during the startup; high-voltage current sources ar e turned on and provide the start-up current as well as charge the vcc capacitor. when the vcc voltage is higher than the uvlo (on) threshold, the high-voltage current source will be turned off. its leakage current is very low (8ua), which only consumes little power. by using such configuration, the traditional startup resistor is not needed and turn-on delay time will be almost the same no matter what the line voltage conditions are (refer to fig. 13). fig. 13 a hysteresis uvlo comparator is implemented in GR8876, and then the turn-on and turn-off threshold levels are fixed at 14.5v and 9v respectively. this hysteresis shown in fig.13 ensures that the start-u p capacitor will be adequate to supply the chip durin g start-up. oscillator the maximum duty-cycle of internal oscillator is limited to about 75% to avoid the transformer saturation. the frequency of the oscillator is decided by an external resistor connected from rt pin to ground. fosc = 6500(khz)/r(kohm). where r is the resistor connected at rt pin. a 100kohm resistor results in 65khz switching frequency. the recommended range of oscillation frequency is 50 khz ~ 130 khz. green-mode operation when the load decreases to an extent, the frequency of the controller will decrease so as to reduce the system power consumption. the minimum frequency is about 22 khz which is outside the audio range. leading-edge blanking (leb) each time the power mosfet is switched on, a turn-on spike will inevitably occur at the sensor resistor. to avoid fault trigger, a 250ns leading- edge blanking time is built in. conventional rc filtering can therefore be omitted. during this blanking period, the current-limit comparator is disabled and cannot switch off the gate driver. internal slope compensation a built-in slope compensation circuit is constructe d in GR8876. when the switch is on, a ramp voltage is added to the sensed voltage across the cs pin, which helps to stabilize the system and prevent sub-harmonic oscillations. gate clamp/soft driving driver is clamped by an internal 18v zener diode. those damages usually come from undesired over-voltage gate signals. under the conditions listed below, the gate output will turn off immediately to protect the power circuit.
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 8 GR8876 the GR8876 also has soft driving function to minimize emi. soft start during initial power on, the GR8876 provides soft start function. it effectively suppresses the star t up peak current to reduce the power mosfet drain voltage especially at high line. over-load protection (olp) the controller has an over load protection function . an internal circuit detects the comp pin level, whe n the level is larger than a threshold and the condit ion lasts more than 60ms, then the gate output will kee p low level. the vcc will decrease to uvlo off level and the controller will be reset again. fig.14 show s the waveform of the olp operation. fig.14 over-voltage protection (ovp) on vcc to prevent power mosfet from being damaged, the GR8876 is implemented an ovp function on vcc. when the vcc voltage is higher than the ovp threshold voltage, the output gate driver circu it will be shut down immediately to stop the switching of power mosfet. the vcc ovp function is an auto-recovery type. if the ovp condition happens, the out pin will be disabled and will recover at th e next uvlo (on). the vcc is working in hiccup mode. fault protections there are several critical protections integrated i n the GR8876 to prevent the power supply or adapter from being damaged. those damages usually come from open or short condition on the pins of GR8876. under the conditions listed below, the gate output will turn off immediately to protect the power circ uit: . gate pin short to ground . cs pin floating . rt pin floating . rt pin short to ground
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 9 GR8876 typical application circuit
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 10 GR8876 bom list no. part description quan. 1 bd1 bridge, kbl406, dip 1 2 c1 x-cap, 0.47uf, 275v, dip 1 3 c2, c14, c20,c21 n.a. 4 c3 cap,102,1kv, dip 1 5 c4 cap,101,50v, smd 0805 1 6 c5 y-cap, cd222, 275v 1 7 c6, c11, c12,c19 cap,103,50v, smd 0805 4 8 c7 cap,104,50v, smd 0805 1 9 c8 cap,102, 200v, smd 0805 1 10 c9 cap, 225, 50v, smd 0805 1 11 c10 cap, 221, 50v, smd 0805 1 12 c13 e-cap,120uf, 400v, 105 , dip 1 13 c15 e-cap, 22uf, 50v, 105 , dip 1 14 c16, c17 e-cap, 680uf, 25v, 105 , dip, low esr 2 15 c18 e-cap, 220uf, 25v, 105 ,dip, low esr 1 16 cn1 ac input (3 pin) 1 17 cr1 fr107, dip 1 18 cr2 1n4148, smd 1 19 cr3 fr104, dip 1 20 cr4, cr5 n.a. 21 cr6 sbr10u100ct 1 22 cr7 iss181, smd 1 23 f1 3.15a, 250v, dip 1 24 hs1 heat sink of rectifier 1 25 hs2 heat sink of mosfet 1 26 j1, j2, j3 0r, smd0805 3 27 j4, j5 0r, smd1206 2 28 l1 common chock, 700uh, dip 1 29 l2 common chock,10mh, dip 1 30 l3 1.6uh, dip 1 31 ntc1 n.a. 32 ntc2 n.a.
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 11 GR8876 bom list (cont.) 33 pcb fr4, 102mm*39.0mm*1.0mm 1 34 q1 fpqf10n60,t0220 1 35 q2 n.a. 36 q3 n.a. 37 r1a, r1b 1m, 5 , smd1206 2 38 r2, r7, r8, r11, r14, r17, r32 n.a. 39 r3a, r3b n.a. 40 r4a, r4b, r5a, r5b 68k, 5 , smd1206 4 41 r6, r33, r34 0r, smd0805 3 42 r9 0.33r, 1w, 1 , rcs 1 43 r10 2.2r, 5 , smd1206 1 44 r12 100k, 1 , smd0805 1 45 r13 33r, 5 , smd0805 1 46 r15a, r15b 22r, 5 , smd1206 2 47 r16 0.0170r, 4.0mm 1 48 r18 68k, 1 , smd0805 1 49 r19 62k, 5 , smd0805 1 50 r20 100r, 5 , smd0805 1 51 r21 1.5k, 5 , smd0805 1 52 r22 10r, 5 , smd0805 1 53 r23 2.2k, 5 , smd0805 1 54 r24 16.5k, 1 , smd0805 1 55 r25, r26 5k, 1 , smd0805 2 56 r28 15k, 5 , smd0805 1 57 r29,r30 4.3k,1 , smd0805 2 58 r31 1.5k, 1 , dip 1 59 t1 p0t-3019, 550uh 1 60 u1 GR8876, sop-8 1 61 u2 pc817, dip-4 1 62 u3 tsm103, sop-8 1 63 zd1 n.a.
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 12 GR8876 package information sop-8 millimeters inches symbol min. max. min. max. a 1.75 0.069 a1 0.10 0.25 0.004 0.010 a2 1.25 0.049 b 0.31 0.51 0.012 0.020 c 0.17 0.25 0.007 0.010 d 4.80 5.00 0.189 0.197 e 5.80 6.20 0.228 0.244 e1 3.80 4.00 0.150 0.157 e 1.27 bsc 0.050 bsc h 0.25 0.50 0.010 0.020 l 0.40 1.27 0.016 0.050 0 o 8 o 0 o 8 o
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 13 GR8876 package information dip-8 millimeters inches symbol min. max. min. max. a 5.33 0.210 a1 0.38 0.015 a2 2.92 4.95 0.115 0.195 b 0.36 0.56 0.014 0.022 b2 1.14 1.78 0.045 0.070 c 0.20 0.35 0.008 0.014 d 9.01 10.16 0.355 0.400 d1 0.13 0.005 e 7.62 8.26 0.300 0.325 e1 6.10 7.11 0.240 0.280 e 2.54 bsc 0.100 bsc ea 7.62 bsc 0.300 bsc eb 10.92 0.430 l 2.92 3.81 0.115 0.150
2009.06 ver. 1.2 copyright grenergy opto, inc. www. grenergy-ic.com 14 GR8876 carrier tape & reel dimensions sop- 8 application a h t1 c d d w e1 f 330.0 2.0 50 min. 12.4+2.00 -0.00 13.0+0.50 -0.20 1.5 min. 20.2 min. 12.0 0.30 1.75 0.10 5.5 0.05 p0 p1 p2 d0 d1 t a0 b0 k0 sop-8 4.0 0.10 8.0 0.10 2.0 0.05 1.5+0.10 -0.00 1.5 min. 0.6+0.00 -0.40 6.40 0.20 5.20 0.20 2.10 0.20 (mm) devices per unit application carrier width cover tape width devices per reel sop- 8 12 - 2500 ___________________________________________________ _____________________ grenergy opto, inc. reserves the right to make corr ections, modifications, enhancements, improvements, and other changes to its products and services at any time and to dis continue any product or service without notice. cus tomers should obtain the latest relevant information before placing orders a nd should verify that such information is current a nd complete.

▲Up To Search▲

Price & Availability of GR8876

	To Download GR8876 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .