GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 1 www.gammamicro.com (top view) pin assignment out supply voltage operating range from 1.8 to 15 v low current consumption: 5.5 ma (typical) operating, 1 a or less stand-by high speed operation up to 1 mhz error amplifier gain is set in the chip to minimize peripheral components soft-start circuit on-chip timer-latch short-circuit detection circuit (scp) on-chip totem-pole output with adjustable on/off current for npn transistors stand-by function sop-8, sol-8 and ssop-8 packages available the GM7001 is a single-channel low-voltage switching regulator control ic with soft-start function and short-circuit detection, capable of 1mhz operation. with its low minimum operating voltage of 1.8v and minimal current consumption, the GM7001 is ideal for power supplies in battery-operated equipment. 1 2 3 4 8 7 6 5 gnd osc fb -in scp v cc br/ctl . o n n i p l o b m y s o / i n o i t p i r c s e d 1n i -i n i p t u p n i g n i t r e v n i r e i f i l p m a r o r r e 2p c s- n i p n o i t c e n n o c r o t i c a p a c g n i t t e s p c s d n a t r a t s t f o s 3v c c - n i p y l p p u s r e w o p 4l t c / r bi n i p l o r t n o c d n a g n i t t e s t n e r r u c t u p t u o 5t u oo n i p t u p t u o e p y t e l o p - m e t o t 6d n g- n i p d n u o r g 7c s o- y c n e u q e r f n o i t a l l i c s o e h t g n i t t e s r o f n i p n o i t c e n n o c r o t s i s e r d n a r o t i c a p a c 8b fo n i p t u p t u o r e i f i l p m a r o r r e
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 2 www.gammamicro.com + - + + + - 1 2 4 3 5 6 7 8 reference voltage supply sawtooth wave oscillator 500 ? 36 k ? 30 k ? output drive control circuit soft start s c p dtc 0.6 v 1.25 v 0.3 v pwm comp. 0.1 v 0.5 v error amp. 0.6 v? 0.1 v? out gnd osc fb -in scp v cc br/ctl block diagram r e t e m a r a p l o b m y s n o i t i d n o c n i m x a m s t i n u e g a t l o v y l p p u s r e w o p v c c --6 1v t n e r r u c e c r u o s t u p t u o i o + - - 0 5 -a m t n e r r u c k n i s t u p t u o i o - --0 5a m e l b a w o l l a n o i t a p i s s i d p d t , 8 - p o s a # # # # # c 5 2 + -* 0 7 5w m t , 8 - p o s a # # # # # c 5 2 + - * 0 3 4w m t , 8 - p o s s a # # # # # c 5 2 + -* 0 8 5w m e r u t a r e p m e t g n i t a r e p o t r p o -0 3 -5 8 +c e r u t a r e p m e t e g a r o t s t g t s -5 5 -5 2 1 +c absolute maximum ratings t a =25 c * note: when mounted on a 10 cm square double-sided epoxy board the devices can be permanently damaged by application of stress (voltage, current,temperature, etc.) in excess of absolute maximum ratings. do not exceed these ratings. refer to recommended operating conditions, page 3.
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 3 www.gammamicro.com r e t e m a r a p l o b m y s . n i m . p y t . x a m t i n u e g a t l o v y l p p u s r e w o p v c c 8 . 1?5 1v e g a t l o v t u p n i r e i f i l p m a r o r r e v i 2 . 0 ??0 . 1v e g a t l o v t u p n i n i p l t c / r b v r b 2 . 0 ?? v c c v t n e r r u c e c r u o s t u p t u o i o + 0 4 ???a m t n e r r u c k n i s t u p t u o i o ? ?? 0 4a m e c n a t i c a p a c n i p p c s c e p ?1 . 0? : f e c n a t i c a p a c n o i t a s n e p m o c e s a h p c p ?1 . 0? : f e c n a t s i s e r g n i t t e s t n e r r u c t u p t u o r b 0 5 10 9 30 0 0 5 s e c n a t s i s e r g n i m i t r t 0 . 10 . 30 . 0 1 k s e c n a t i c a p a c g n i m i t c t 0 0 10 7 20 0 0 0 1f p y c n e u q e r f n o i t a l l i c s o f c s o 0 10 0 50 0 0 1z h k e r u t a r e p m e t g n i t a r e p o t p o 0 3 ?5 2 +5 8 +c recommended operating conditions note: ?recommended operating conditions? are normal operating ranges for the device. all the device?s electrical characteris tics are guaranteed when operated within these ranges. operation outside the recommended ranges may adversely affect reliability and co uld result in device failure. no warranty is made with respect to uses, operating conditions, or combinations not represented on th e data sheet.
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 4 www.gammamicro.com electrical characteristics (t a = 25o c, v cc =+2v) r e t e m a r a p l o b m y s n o i t i d n o c . n i m . p y t . x a m t i n u t n e v e r p o t t i u c r i c t u p n i w o l t a n o i t c n u f l a m ) . o . l . v . u ( e g a t l o v e g a t l o v t e s e r v r ? ?? 9 . 0v e g a t l o v d l o h s e r h t v h t 1 . 13 . 15 . 1v t r a t s t f o s t n e r r u c g n i g r a h c i s c v p c s v 0 = 5 . 1 ?0 . 1 ?7 . 0 ? : a t l o vn o i t e l p m o c t r a t s t f o s t a e g a v s t ?7 . 08 . 09 . 0v n o i t c e t e d t i u c r i c t r o h s ) p c s ( t n e r r u c g n i g r a h c i c p c v p c s v 0 = 5 . 1 ?0 . 1 ?7 . 0 ? : a e g a t l o v d l o h s e r h t v c p t ?7 . 08 . 09 . 0v r o t a l l i c s o e v a w h t o o t w a s ) c s o ( y c n e u q e r f n o i t a l l i c s o f s c o r t 0 . 3 =k s c , t f p 0 7 2 = 0 0 40 0 50 0 6z h k y t i l i b a t s t u p n i y c n e u q e r f f v d v c c v 5 1 o t v 2 = ?2 0 1% n o i t a i r a v y c n e u q e r fwp m e t h t i. f t d t a c 5 8 + o t c 0 3 ? = ?5?% r e i f i l p m a r o r r e e g a t l o v d l o h s e r h t t u p n i v t v b f v m 0 5 4 = 0 8 40 0 50 2 5v m y t i l i b a t s t u p n i t v v v d t v c c v 5 1 o t v 2 = ?5 0 2v m . p m e t h t i w n o i t a i r a v t v v t d t t a c 5 8 + o t c 0 3 ? = ?1?% t n e r r u c s a i b t u p n i i b v n i v 0 = 0 . 1 ?2 . 0 ?0 . 1 : a n i a g e g a t l o v a v ?0 70 0 15 4 1v / v h t d i w d n a b y c n e u q e r fw b a v b d 0 = ?6? z h m t u p t u o m u m i x a m e g n a r e g a t l o v v m o + ? 8 7 . 07 8 . 0?v v m o ? ?5 0 . 02 . 0v t n e r r u c e c r u o s t u p t u o i m o + v b f v 5 4 . 0 = ?0 4 ?4 2 ? : a t n e r r u c k n i s t u p t u o i m o ? 4 20 4? : a d o i r e p e l d i n o i t c e s t n e m t s u j d a e l c y c y t u d m u m i x a m t y t u d r t 0 . 3 =k s c , t v , f p 0 7 2 = b f v 8 . 0 = 5 65 75 8% n o i t c e s t u p t u o e g a t l o v t u p t u o v 1 h o r b 0 9 3 = s i , o a m 5 1 ? = 0 . 12 . 1?v v 2 h o r b 0 5 7 = s v , c c i , v 8 . 1 = o a m 0 1 ? = 8 . 00 . 1?v v 1 l o r b 0 9 3 = s i , o a m 5 1 = ?1 . 02 . 0v v 2 l o r b 0 5 7 = s v , c c 8 . 1 =, vi o a m 0 1 = ?1 . 02 . 0v t n e r r u c e c r u o s t u p t u o i o +r b 0 9 3 = s v , o v 9 . 0 = ?0 3 ?0 2 ?a m t n e r r u c k n i s t u p t u o i o ?r b 0 9 3 = s v , o v 3 . 0 = 0 30 6?a m e c n a t s i s e r n w o d l l u p r o ?0 20 30 4 k s g n i t t e s t n e r r u c t u p t u o n o i t c e s l o r t n o c / n o i t c e s e g a t l o v n i p v r b r b 0 9 3 = s 2 . 03 . 04 . 0v n o i t i d n o c f f o t u p n i i f f o ? 0 2 ??0 : a n o i t i d n o c n o t u p n i i n o ?? 5 4 ? : a e g n a r t n e r r u c n i p i r b 8 . 1 ??1 . 0 ?a m e c i v e d e r i t n e t n e r r u c y b - d n a t s i s c c v r o n e p o n i p l t c / r b c c ?? 1 : a t n e r r u c y l p p u s e g a r e v a i c c r b 0 9 3 = s ?5 . 53 . 9a m
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 5 www.gammamicro.com setting the time constant for soft start and short circuit detection 1. soft start at power on, the capacitor c pe connected to the scp pin begins charging. the pwm comparator compares the soft start setting voltage (as a proportion of the voltage at the scp pin) with the sawtooth waveform. this comparison controls the on duty of the out pin, causing soft start operation. upon completion of soft start operation, the voltage at the scp pin remains low, the soft start setting voltage remains high, and the circuit enters into output short circuit detection wait state. soft start time (the time until the output on duty reaches approximately 50%) t s [s] ? 0.35 c pe [ f] 2. short circuit protection if the switching regulator output suddenly drops due to load effect, the error amplifier output (fb pin) is fixed at v om + and capacitor c pe begins charging. when the voltage at the scp pin reaches approximately 0.8v, the output pin is set low and the scp pin remains low. once the protection circuit activates, operation of the circuit can be restored by resetting the power supply. short circuit detection time t pe [s] ? 0.8 c pe [ f] measurement circuit diagram -in 18 k ? 2 k ? 390 ? 10 f 22 h GM7001 4 5 v out i out v cc (5 v)
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 6 www.gammamicro.com application example 10 f v out 18 k ? 3 k ? (5 v) 22 h v in (3v) 0.1 f 2 k ? 0.1 f 270pf 390 ? 33 f out gnd osc fb -in scp v cc br/ctl 8 7 6 5 1 2 3 4 ctl 3. other functions (1) soft start and short circuit detection soft start operation is set by connecting capacitor cpe to the scp pin (pin 2). soft start prevents a current spike on start-up. upon completion of the soft start, the scp pin (pin 2) remains low and begins the short circuit detection wait state. when an output short circuit occurs, the error amplifier output is fixed at v om + and capacitor cpe starts charging. after charging to approximately 0.8 v, the output pin (pin 5) is set low and the scp pin (pin 2) stays low. when the protection circuit is activated, operation of the circuit is restored by resetting the power supply. (2) circuit to prevent malfunction at low input voltage the GM7001 is protected against voltage transients at power-on, or instantaneous glitches in the supply voltage which could lead to malfunction of the control ic and cause system damage or failure. the GM7001?s protection circuit to prevent malfunction at low input voltage detects a low input voltage by comparing the supply voltage to the internal reference voltage. on detection, the circuit sets the output pin to low. the GM7001 recovers when the supply voltage rises above the threshold voltage of the malfunction prevention circuit.
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 7 www.gammamicro.com power supply control function stand-by mode (supply current 1 a or less) can be set by connecting the br/ctl pin (pin 4) to v cc or by making the pin open circuit. w s e d o m f f oe d o m y b - d n a t s n oe d o m g n i t a r e p o GM7001 br/ctl 4 rb sw switching regulator function (1) reference voltage circuit the reference voltage circuit generates a temperature-compensated reference voltage ( ? 1.25v) from voltage supplied via the power supply pin (pin 3). besides providing the reference voltage for the switching regulator, the circuit sets the idle period. (2) sawtooth wave oscillator the sawtooth oscillator generates a sawtooth wave (up to 1 mhz) that is stable with respect to supply voltage and temperature. the capacitor and resistor that set the oscillation frequency are connected to osc (pin 7). (3) error amplifier the error amplifier detects the output voltage of the switching regulator and outputs the pwm control signal. the voltage gain is fixed, and connecting a phase compensation capacitor to fb (pin 8) provides stable phase compensation for the system. (4) pwm comparator the voltage comparator has one inverting and three non-inverting inputs. the comparator is a voltage/pulse-width converter that controls the on time of the output pulse depending on the input voltage. the output level is high (h) when the sawtooth wave is lower than the error amplifier output voltage, soft-start setting voltage, and idle period setting voltage. (5) output circuit the totem pole output circuit can drive an external npn transistor directly. the value of the on/off current is set by a resistor connected to br/ctl (pin 4). . 1 0 0 7 m g e g a k c a p . o n t r a p 8 - p o s8 s 1 0 0 7 m g 8 p o s m8 m 1 0 0 7 m g ordering information
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 8 www.gammamicro.com sop-8 package outline dimensions l o b m y s s r e t e m i l l i m n i s n o i s n e m i ds e h c n i n i s n o i s n e m i d n i mx a mn i mx a m a5 4 . 15 7 . 17 5 0 . 09 6 0 . 0 1 a1 . 05 2 . 04 0 0 . 01 0 . 0 2 a5 3 . 15 5 . 13 5 0 . 01 6 0 . 0 b6 0 3 . 06 0 5 . 02 1 0 . 02 0 . 0 c3 5 1 . 03 5 2 . 06 0 0 . 01 0 . 0 d1 8 . 41 0 . 59 8 1 . 07 9 1 . 1 e4 8 . 34 0 . 41 5 1 . 09 5 1 . 0 1 e4 8 . 54 2 . 63 2 . 06 4 2 . 0 e7 2 . 15 0 . 0 l5 4 . 018 1 0 . 09 3 0 . 0 0 8 0 8
GM7001 bipolar low voltage switching regulator controller revision 1, may 2002 9 www.gammamicro.com msop-8 package outline dimensions l o b m y s s r e t e m i l l i m n i s n o i s n e m i d s e h c n i n i s n o i s n e m i d n i mm o nx a mn i mm o nx a m a1 8 . 02 0 . 12 1 . 12 3 0 . 00 4 0 0 . 08 4 0 . 0 1 a5 0 . 05 1 . 02 0 0 . 06 0 0 . 0 2 a6 7 . 06 8 . 07 9 . 00 3 0 . 04 3 0 . 08 3 0 . 0 b8 2 . 00 3 . 08 3 . 01 1 0 . 02 1 0 . 05 1 0 . 0 c3 1 . 05 1 . 03 2 . 05 0 0 . 06 0 0 . 09 0 0 . 0 d0 9 . 20 0 . 30 1 . 34 1 1 . 08 1 1 . 02 2 1 . 0 e0 7 . 40 9 . 40 1 . 55 8 1 . 03 9 1 . 01 0 2 . 0 1 e0 9 . 20 0 . 30 1 . 34 1 1 . 08 1 1 . 02 2 1 . 0 e5 6 . 06 2 0 . 0 l0 4 . 03 5 . 06 6 . 06 1 0 . 01 2 0 . 06 2 0 . 0 y0 1 . 04 0 0 . 0 0 6 0 6 note 1. package body sizes exclude mold flash and gate burrs 2. dimension l is measured in gage plane 3. tolerance 0.10 mm unless otherwise specified 4. controlling dimension is millimeter. converted inch dimensions are not necessarily exact. 5. design following jedec mo-187.
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