GR1210CG

GR1210 Multi-Mode PWM Controller with Primary-Side Feedback Features Description  Low Start-Up Current (VsG1)* Soft Start Time (CS Pin) Soft Start Time* GATE DRIVER OUTPUT (OUT Pin) Output low level, VCC = 15V, Io = 10mA VOL 0 Output high level, VCC = 15V, Out pin=1.5kΩ to GND VOH1 8 Output High Level, VCC=UVLO-OFF+0.2V VOH2 7 1 V V VCC V Rising time, load capacitance = 1000pF* Rising 430 ns Falling time, load capacitance = 1000pF* Falling 75 ns VOC1 13.5 V TMAX_ON 10.8 μs 145 ℃ 30 ℃ VGATE-clamp (VCC = 17V )* Maximum On Time (CCM Fs=70kHz) Internal OTP (Guaranteed by design) OTP* Hysteresis* *Guaranteed by Design. 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 6 GR1210 5 17 4 16.5 UVLO (ON) (V) Istartup( uA ) Typical Performance Characteristics 3 2 16 15.5 1 15 14.5 0 -40 0 -40 120 Istartup current vs. Temperature 40 80 120 Fig. 2 UVLO (ON) vs. Temperature 9 68 8.5 66 8 7.5 7 64 62 60 6.5 58 -40 0 40 80 Temperature(℃) 120 -40 Fig. 3 UVLO (OFF) vs. Temperature 0 40 80 Temperature(℃) 120 Fig. 4 CCM Frequency vs. Temperature 27 0.9 26 0.88 Vcsmax (V) Green Mode Frequency(kHz) 0 Temperature(℃) Frequency(kHz) UVLO (OFF) (V) Fig. 1 40 80 Temperature(℃) 25 24 0.86 0.84 0.82 23 0.8 22 -40 0 40 80 Temperature(℃) 120 Fig. 5 Green Mode Frequency vs. Temperature -40 0 40 80 120 Temperature(℃) Fig. 6 Vcsmax vs. Temperature 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 7 GR1210 0.74 4.6 0.72 4.4 Vcomp (open) ( V ) VcsmaxL (V) Typical Performance Characteristics 0.7 0.68 0.66 4.2 4 3.8 0.64 3.6 -40 0 40 80 120 -40 0 Temperature(℃) Fig. 7 VcsmaxL vs. Temperature 80 120 Fig. 8 Vcomp open loop voltage vs. Temperature 30.5 2.55 29.5 2.53 28.5 2.51 Vref (V) VCC OVP ( V ) 40 Temperature(℃) 27.5 26.5 2.49 2.47 2.45 25.5 -40 0 40 Temperature(℃) 80 Fig. 9 VCC OVP vs. Temperature 120 -40 0 40 80 120 Temperature(℃) Fig. 10 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com Vref vs. Temperature 8 GR1210 Application Information the on-time TON is increased, and thus the switching Overview The GR1210 is a high performance multi-mode (QR/CCM) primary side feedback controller for flyback converter. This results in a low-cost solution for low power AC/DC adapters. It integrated more functions to reduce the external components counts and the size. Its major features are described as frequency decreases. If the switching frequency lowers than 65kHz frequency, the controller adaptively transitions to a CCM mode. Thus, small size transformer can be used with high power conversion efficiency. As the output load current is decreased, the on-time TON is decreased, and thus the switching frequency below. increases. If the switching frequency increases till Start-up Current over the clamp of 69kHz, IC will skip the first valley The typical start-up current is 1.5uA. Very low to turn on in 2 nd rd or 3 valley. start-up current allows the PWM controller to At light load conditional, the VCOMP is lower than increase the value of start-up resistor and then VSG1 and the system operates in green mode for reduce the power dissipation on it. high Under-voltage Lockout (UVLO) switching frequency clamp will start to linearly A hysteresis UVLO comparator is implemented in decrease from 69kHz to 25kHz. The valley GR1210, then the turn-on and turn-off thresholds switching characteristic is still preserved in green level are fixed at 16V and 7.5V respectively. This mode. That is, when load decreases, the system hysteresis shown in Fig.13 ensures that the start-up automatically skip more and more valleys and the capacitor will be adequate to supply the chip during switching frequency is thus reduced. start-up. At zero load or very light load conditions (Vcomp< power conversion efficiency. The max VSP1), the max switching frequency clamp will Vcc linearly decrease from 25kHz to 0.4kHz, enhancing power saving. UVLO (on) Frequency Improve light load eff. UVLO (off) Lower switching loss Lower conduction loss 69 K 65K 25K Green Mode Fig.13 Multi-Mode Operation for High Efficiency 0.4K PFM Mode VSP2 Valley Skip VSP1 VSG2 GR1210 is a multi-mode QR/CCM controller. The QR Mode VSG1 Fix Frequency CCM COMP Fig.14 controller changes the mode of operation according to switching frequency and comp pin voltage, as shown in the Fig.14. At the normal operating condition, the IC operates in QR mode to reduce the Quasi-Resonant Detection The QR detection block will detect auxiliary winding voltage to turn on the MOSFET. switching loss. In the QR mode, the frequency varies depending on the line voltage and the load conditions. As the output load current is increased, 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 9 GR1210 Leading-edge Blanking (LEB) AC Input Ns Each time the power MOSFET is switched on, a Vout turn-on spike will inevitably occur at the sense Na resistor. To avoid fault trigger, a leading-edge blanking time is built in. During this blanking period, VCC Ra OUT the current-limit comparator is disabled and cannot Logic FB switch off the gate driver. S/H Gm Vref Internal Slope Compensation Rb GND CS COMP A built-in slope compensation circuit is constructed in GR1210. When the switch is on, a ramp voltage Fig.15 is added to the sensed voltage across the CS pin, which helps to stabilize the system and prevent Load Regulation Compensation sub-harmonic oscillations. In GR1210, the load regulation compensation is Constant Voltage Operation implemented to achieve good voltage regulation. An GR1210 senses the auxiliary winding on the offset voltage is generated at FB pin by an internal primary-side to regulate the output voltage, as current flowing into the resister divider. The internal shown in the Fig. 15. The auxiliary winding voltage sink current source is proportional to the value of is a reflection of the output voltage while the load current. It can also be programmed by MOSFET is in off state. Via a resistor divider adjusting the resistance of the voltage divider to connected between the auxiliary winding and FB pin, compensate the drop for various cable lines used. the auxiliary voltage is sampled after the sample Over-voltage Protection (OVP) on VCC Auto delay time and will be hold until the next sampling period. The internal error amplifier compares the sampled voltage with an internal reference Vref (2.5V) and the error will be amplified. The error amplifier output COMP controls the duty cycle to regulate the output voltage, thus constant output voltage can be achieved. The output voltage is To prevent power MOSFET from being damaged, the GR1210 is implemented an OVP function on VCC. When the VCC voltage is higher than the OVP threshold voltage, the output gate driver circuit will be shut down immediately to stop the switching of power MOSFET. The VCC OVP function is an given as: Vout Recovery mode  Ra  N s   2.51   VF   Rb  N a  Where VF indicates the drop voltage of the output diode, Ra and Rb are top and bottom feedback auto-recovery type protection. If OVP happens, the pulses will be stopped and recover at the next UVLO on. The GR1210 is working in a hiccup mode as shown in Fig. 16. resistor value, Ns and Na are the turns of transformer secondary and auxiliary. The leakage inductance of transformer will induce ringing to affect output regulation. To optimize the snubber circuit will minimize the high frequency ringing and achieve the best regulation. 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 10 GR1210 FB Pin Short Protection– Auto Recovery mode VCC To protect the circuit from damage due to FB short OVP Tripped OVP Level condition, an auto-recovery type of FB short UVLO(on) protection is implemented for it. Since the FB pin UVLO(off) t OUT voltage is clamped at 0 V when the MOSFET is turned on. The FB pin current is used for FB short protection. When FB is short over the 4 switching Non-Switching Switching cycles, FB short protection is triggered. Switching t Fig.16 Gate Clamp/Soft Driving Driver output is clamped by an internal 13.5V Output Under-voltage Protection (UVP) on FB– clamping circuit to prevent from undesired over-voltage gate signals. And under the conditions Auto Recovery mode listed below, the gate output will turn off immediately To protect the circuit from damage due to output short condition, an auto-recovery type of UVP to protect the power circuit. The GR1210 also has soft driving function to minimize EMI. protection is implemented for it. If the FB voltage declines below 1V for over the 8ms, the protection will be activated to turn off the gate until the next Fault Protection UVLO-ON. There are several critical protections integrated in the . CS pin floating NAUX . FB pin shorting (Rb shorting) Ra 1V FB S/H + - UVP Debounce 8ms . FB pin Open (Ra and Rb Open) . Ra Open Rb Fig.17 OUT FB Sample Fig.18 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 11 GR1210 Package Information SOT-26 SOT-26 SYMBOL MILLIMETERS MIN. INCHES MAX. A MIN. MAX. 1.45 0.057 A1 0.00 0.15 0.000 0.006 A2 0.90 1.30 0.035 0.051 b 0.30 0.50 0.012 0.020 c 0.08 0.22 0.003 0.009 D 2.70 3.10 0.106 0.122 E 2.60 3.00 0.102 0.118 E1 1.40 1.80 0.055 0.071 e 0.95 BSC 0.037 BSC e1 1.90 BSC 0.075 BSC L θ 0.30 o 0 0.60 8 o 0.012 o 0 0.024 8 o Note: 1. Followed from JEDEC MO-178 AB. 2. Dimension D and E1 do not include mold flash, protrusions or gate burrs. Mold flash, protrusions or gate burrs shall not exceed 10 mil per side 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 12 GR1210 Carrier Tape & Reel Dimensions SOT-26 Application A H 178.0±2.00 50 MIN. P0 P1 P2 D0 D1 4.0±0.10 4.0±0.10 2.0±0.05 1.5+0.10 -0.00 1.0 MIN. SOT-26 Application SOT -26 T1 C d 8.4+2.00 13.0+0.50 1.5 MIN. -0.00 -0.20 D W E1 20.2 MIN. 8.0±0.30 1.75±0.10 T A0 B0 F 3.5±0.05 K0 0.6+0.00 -0.40 3.20±0.20 3.10±0.20 1.50±0.20 Carrier Width Cover Tape Width Devices Per Reel 8 5.3 3000 (mm) 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 13 GR1210 Tape and Specification Reel SOT 26 Direction of feed ________________________________________________________________________ Nanjing Greenchip Semiconductor Co., Ltd. reserves the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. 2018.01. Ver.1.0 Copyright Nanjing Greenchip Semiconductor Co., Ltd. www.grenergy-ic.com 14